Littermate Syndrome: The risky downside to raising sibling puppies

By Jeff Stallings, CPDT-KA

Upon reading Patricia Leslie’s email, I knew I’d be replying with disappointing news. “We were planning to adopt one puppy, but the breeder said that raising two sisters would be easier.” Leslie had contacted me after reading my blog post about littermate syndrome, in which profoundly bonded siblings have difficulty relating to humans and other dogs.

“After we brought the mixed-breed girls home at nine weeks, their behavior grew completely out of control. My husband and I could not get their attention for more than a second or two, as if we weren’t even in the same room. And then they started displaying alarming fearfulness of people and other dogs.” I made an appointment to meet Patricia, her husband Karl and the puppies the next day at their Richmond, California home.

Many dog behaviorists, trainers, breeders and shelters discourage adopting siblings. Anecdotal evidence suggests that behavioral issues may arise during key development periods because the two puppies’ deep bond impedes their ability to absorb and grasp the nuances of human and canine communication. Since fear is the default reaction to odd or unfamiliar stimuli in dogs, this muddled understanding of the world around them can lead to impaired coping mechanisms later on. Many factors influence behavior and not all siblings raised together will exhibit signs: Littermate syndrome is a risk, not a foregone conclusion.

Littermate Syndrome

Common Signs
Signs include fearfulness of unfamiliar people, dogs and other novel stimuli (neophobia); intense anxiety when separated even briefly; and difficulty learning basic obedience skills. In some cases the two dogs fight incessantly. Over lunch recently, veterinarian and dog behaviorist Dr. Ian Dunbar and I discussed raising sibling dogs. “It’s a disaster waiting to happen for the littermates because they don’t get socialized to other dogs or people, let alone to their owners,” he said. Many owners assume their interacting with each other is adequate, “but when the puppies are five or six months old and meet an unfamiliar dog in a novel setting, they absolutely freak out.”

Dunbar points out that raising littermates necessitates training two puppies—particularly challenging when they essentially wear blinders to all but each other. “It’s more than twice the work; it’s exponential. The two combine to produce levels of energy that we can barely measure. Tension develops in training and compliance as they squeeze the owner out of the relationship. They’re always living with an enormous distraction—each other.”

The Tie That Binds
Cohabitating siblings may become so emotionally dependent on each other that even short separations provoke extreme distress. Behavior specialist and author Nicole Wilde recalls a case in which two nine-year-old sibling Huskies attended her group class. “They were so bonded to each other that I literally could not take one and walk a few feet away to practice loose leash skills because the other would scream.”

Wilde believes the problems are rooted in hyper-attachment, leading to hindered social development and communication issues. “People assume that having two same-age pups that play together and interact constantly covers their dog-dog socialization needs, but they in fact don’t learn how other breeds play and have no idea about social skills with other puppies, adolescents or adult dogs. Perhaps one puppy is a bit of a bully, which his littermate puts up with, but his rude behavior might not be tolerated by a new dog in a new setting.”

During my appointment with Leslie, we determined that the best course was to re-home one of her twelve-week-old siblings. Dunbar agrees that it’s often best to separate littermates, especially if symptoms appear early, so that each has a chance to develop normally as an individual. This is obviously a burdensome decision for the overwhelmed owner to make, a sort of canine Sophie’s Choice, so he recommends that the new owner meet both puppies and determine which to take home.

Together Forever
Owners committed to raising a pair should ensure the puppies spend significant portions of every day apart so that each learns how to be alone—a key lesson in any well thought-out puppy program. This means feeding, walking and training separately, with individual crates in different parts of the home. Even trips to puppy socials and the vet should be separate so that both learn to incorporate these episodes into their psyches without being overly dependent on their littermate.

This separate-but-equal arrangement is time-consuming, exhausting and seems to defeat the original intent of acquiring siblings. Wilde notes that planned separations must begin immediately. “I’ve been called into homes where four-month-old siblings have been sleeping in the same crate for eight weeks and not purposefully separated by the owners, who had the best intentions but were unaware of littermate issues. Even getting the puppies to sleep in separate crates right next to each other is traumatic for them.”

Dunbar, too, is adamant that a key lesson for a puppy to master is how to be content with being alone, all but impossible with two siblings. “Once we’ve done that, yes, he can live with other dogs and have free run of the house. But if you don’t teach puppies early on how to be alone, and especially with siblings who have always been together, it will be catastrophic when one dies.” Dunbar encourages multiple dog households—“I always like having three dogs”—but the timing, temperament and age that each enters the home is paramount.

Most people contacting me through my blog never heard of littermate syndrome before finding the post while researching symptoms observed in their dogs. Increasingly, trainers and behavior professionals recognize that the cons of adopting siblings far outweigh the pros. “The only advantage I can think of is a short-term gain of the puppies being less lonely in the first month of life”, says Dunbar. “Everything else is a loss.”

Exceptions and Hope
While the majority of comments to my blog corroborate struggles in raising siblings—including the ongoing aggression and fighting often seen between same-gendered littermates—others write of well-adjusted cohabitating pairs. A common thread seems to be that littermates are more likely to thrive when introduced into a household with an older dog, who perhaps acts as an arbiter and stabilizing influence.

Myriad factors affect dog behavior, including genetics, early life experiences and owner engagement. As University of California/Davis veterinary behaviorist Dr. Melissa Bain points out, “two fearful littermates very well may be genetically predisposed to fear.” Bain is less inclined to apply the term syndrome to the set of symptoms: “It makes you think all littermates have problems, which is not the case.” She also emphasizes that the level of owner involvement is key, saying “the symptoms escalate when the owners treat them as one dog with eight legs.” When conflict ensues within the pair, Bain believes it’s due to the dogs being too similar in size, age and gender. “This uniformity makes it difficult for the siblings to delineate a hierarchy,” she said.

After Leslie’s second sibling had been re-homed, her remaining puppy began to thrive under a remedial socialization program. “Dora has blossomed in the last three months into a delightful household companion and she continues to improve. She now approaches people out of curiosity. We know she would still be fearful had we not separated the two before it got any worse. Dora has become more confident with all kinds of dogs and successfully completed a group obedience class.”

Increased Awareness
Recognition of the risks appears to be spreading, with many breeders and shelters declining to place siblings together. Shelley Smith, adoption center manager at Pets Unlimited in San Francisco, said her shelter stopped placing siblings together after a particularly disturbing case. “A dachshund mix named Thelma was returned to the shelter because her sibling repeatedly attacked her and she had multiple injuries by the time the heartbroken family returned her to us. Thankfully we were able to re-home Thelma, but it’s almost certain the fighting and anxiety could have been avoided had the two littermates not been placed together. We now separate siblings and inform adopters about the rationale for our policy.”

While siblings blessed with extraordinary genes and socialization-forward owners may deflect littermate syndrome, the consensus among canine professionals is that it’s not worth the risk. Most would encourage new owners to adopt a single puppy that suits their lifestyle and to focus on the training and socialization that strengthens the interspecies bond unique to humans and dogs. Once your puppy is a dog, by all means, get a second since the two will be at completely different stages, and the older one may very well emerge as a great life teacher to the younger.

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About Jeff Stallings, CPDT-KA

Having owned well-trained dogs all my life, I started Better Nature Dog Training to exploit decades of experience teaching across a number of fields. I am nationally-certified through the highly-respected Certification Council for Professional Dog Trainers and am a professional member of the Association of Professional Dog Trainers. I teach people how to effectively train their dogs by clearly demonstrating that every interaction counts when training a dog to come when called, for example, or instructing a puppy how to best get along in life. I take a scientific and holistic approach to dog training. The scientific aspect comes from understanding dog psychology from an evolutionary perspective, knowing how dogs are both similar to and distinct from their ancestors, including the grey wolf. The holistic component derives from taking into account all facets of any particular dog’s situation, including upbringing, prior training, traumatic events and—most importantly—the characteristics of his home and family life. Training a puppy or dog can be a most rewarding life experience; it can also be stressful and perplexing. One of the best services I provide is taking the guesswork out while lending a sure, guiding hand in successful dog behavior development and modification.
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114 Responses to Littermate Syndrome: The risky downside to raising sibling puppies

  1. Sue says:

    That was a brilliant article…..and of course whilst reading it, it all made sense.
    Never too old to learn something new!……thanks!.

  2. Pingback: Adopting Littermate Puppies: Don’t Do It | Quantum Meruit

  3. Kirsti says:

    I am currently experiencing this “Littermate Syndrome” with my 15 month old lab/terrier females. We were completely unaware that such a thing existed and the people at the shelter from which we adopted them mentioned nothing of the such. They actually encouraged us to adopt both puppies. The aggression towards one another just started about a week ago and it is awful. I am heart broken at the thought of having to re-home one of them. Is there any way that they will grow out of trying to over-dominate the other and can eventually live in peace with one another again? Or should we absolutely re-home one of them?

    • Kirsti, I am sorry to hear that. What age were they when you adopted them? I am not sure where you live, but I suggest working with a behavior consultant/trainer to help evaluate all your options.

  4. Vicki Shelton says:

    My husband and I made a huge mistake and purchased two male littermates at the same time. They are now six months old and one of them (Boo) is continually fighting with the other(Bear). Bear is now cowering down when he sees Boo coming toward him. We also have a five year old (Max). These are all German Shepherds. Max has been circling Bear every time Boo comes near. Max is very well trained but is now exhibiting tremendous anxiety. A lot of the time he will not even eat and neither will Bear. I have tried to find a home to no avail and have talked to three trainers about this and all said the same thing—not good at all. Bear had been very playful and confident but doesn’t seem that way now and Max is worn out trying to keep them apart. We cannot separate them due to housing and time issues. We are at wits end. I have put a call in to our local State Police because I was told that sometimes they will take a dog to train for their canine unit. I haven’t heard anything yet. We had never heard of Littermate Syndrome until talking to the trainers. This is horrible! Any suggestions?

    • Yours is unfortunately a classic case. Definitely rehome one of these dogs. I would lean towards keeping Bear since Boo might have a bit more confidence to draw on. You are going to have to spend lots of time working to rebuild Bear’s confidence.

  5. Bonnie Joyce says:

    We adopted 5 yr old beagles who are littermates. We also did not know of the littermate syndrome before the adoption. Is this an ethical hot button in the breeding and adopting communities? What can be done to get the message out better?

    • Bonnie, I am researching this topic and have met with veterinarian behaviorists at UC Davis. I will be interviewing Dr. Ian Dunbar in the coming. I am writing an article on the subject with the target of publication in a national magazine, such as The Bark. I would be interested in talking to you about your experiences.

      • Bonnie Joyce says:

        I am not sure I will be able to add a whole lot to the discussion, but I am willing. How can we set up a contact? (I’m using my fb account this time; the other is a shared account.)

  6. Tom says:

    We adopted two chiapoo puppies. They were 9 weeks old. We originally intended on getting just one but the original owner said we could have both as he needed to get rid of them by the weekend(going on vacation). We quickly saw some aggression. One pup more than the other. They were the center of each others world and got aggitated whenever one of us interrupted their play. We thought it best to sell one. But after seeing your blog, We really started to push the sale. The pups are 12 weeks now and really feel like they need to be separated to be good family pets. Thanks for this article.

    • You’re welcome. I am working on an article about this subject for Bark Magazine right now, hopefully to get the word out so fewer people head down this often-disasterous path.

      • ThePayferPack says:

        When your article is published, will you have a way that other trainers can print it to reference it or hand it out? I see people getting litter mates all the time coming into the store that I am a trainer in. I also have people that ask about it and I think having an article/handout ready and waiting to give to people to take home and read would be helpful in spreading the word. The more that people know the better.

        When I was a pet sitter I had litter mate labs (male/female) and right around one year, I had an incident with them where one became over stimulated after I brought her away from a very “playful” snake and she then started biting at me and while trying to calm her the other joined in. Even though I recommended that they take the pups to training when they were younger, they never did (even after the incident they didn’t take them to training).

        Of course I found out later that the female wasn’t allowed out with the boys because she would get over stimulated and go after them and their friends. I ended up firing them as clients.

      • Thanks for your story and perspective. I am waiting for my interviewees to approve the draft, then it will be up to the magazine (submitting it to three) as to when to print. Feel free to print this article out to hand to folks!

  7. Nan Wells says:

    Excellent article!! It is very true that breeders and rescue shelter groups are encouraging people to adopt two puppies in a litter because they are apparently unaware of this. I had a client that called me that had two foster puppies from the same litter. They experienced severe aggression between the two at less than three months of age. I advise them to take the other puppy back to the rescue group and keep just the one. He’s turned into a wonderful puppy through their socialization and obedience class work.

    Nan Wells
    DogWoods Retreat

    • Thanks for the comments, Nan. I am expanding this article, hopefully for print in Bark Magazine. The word needs to get out!

    • Leeanne Cagnacci says:

      Not all breeders encourage people to buy/adopt two puppies from a litter! I am a breeder and will not let buyers have more than one puppy for the very reasons stated in the article. Reputable breeders won’t let two puppies go to the same home and I certainly will not encourage it to “get rid” (I hate that term, it sounds like the puppies are rubbish that needs discarding) of puppies for any reason.

      • I would think that most breeders would know about this, but many do not. Thanks for your perspective.

      • Julie says:

        Leanne, I take issue with your comment that “reputable breeders won’t let two puppies go to the same home”. I AM a very reputable, responsible breeder and I have in 2 instances over the years, allowed the same family to adopt sibling puppies. Just because you don’t do it, doesn’t mean that others aren’t qualified enough to interview and know well enough that the family they are allowing to adopt is capable of properly socializing multiple puppies at once. I don;t allow it on a regular basis, but in both instances these were large families with 4 or more older children that were both committed to making sure the puppies were socialized separately so they didn’t become too dependent upon each other. In both cases, they ended up being incredible, well behaved family companions. The world is not black and white, so don’t make such close minded, offensive statements.

      • Carol says:

        I agree with Leanne, I am a breeder and do not place two puppies in the same home at the same time. I never “get rid” of puppies, I feel that I am responsible for the puppies I breed, and if they don’t get placed, they stay with me. I also volunteer with a rescue group, we very, very rarely place two dogs at one time unless they come to us as a bonded pair. Get one dog socialized to your home and lifestyle and then add another if you wish.

  8. Kristin says:

    I rescued 2 female Jack Russell mix litter mates 10 years ago. I really wish someone had told me then not to adopt both of them. I love both of my girls dearly but having them has definitely been a trial through the years. I’ll be honest and say I don’t think I have many of the syndromes problems, but I do have my fair share. They are both food aggressive especially with each other & that is what usually causes their fights. And good lord when they fight!!! There is ALWAYS wounds after their fights. Some have been bad enough that I’ve had to take them to the vet for stitches and deep cleaning of puncture wounds. My girls aren’t big (both about 30 lbs), but when they’re fighting it can take me up to 15 mins to break them apart. They are both very strong & focus so much on fighting that they don’t even realize I’m there. I’ve been bit a couple times while trying to break up the fights but thankfully nothing a good cleaning and a bandage couldn’t fix.

    I volunteer with a rescue organization now and often tell people NOT to get litter mates. Then I go into some of the stories I have about what I’ve gone through. I will absolutely never make that mistake again but at this point in their lives I won’t rehome either one. I couldn’t do that to them…or myself. I know that I’m fortunate that for the most part they tend to get along and play well together. But I will never never never have litter mates EVER again. I do want to thank you for this article as it finally validates what I’ve been saying for years…NO LITTER MATES EVER!!

    • Hello Kristin, thanks for your contribution to the subject and for helping to confirm that this condition is real, common and, ultimately, avoidable. I would never suggest that you separate them after this many years together. Lots of management, as you well know.

      This blog post has become a de facto source of information, apparently. Hits to this particular post have increased exponentially each month it’s been up. To that end, and to get the word out, I am working on an expanded article, hopefully destined for print in a national magazine so that more people are aware.

      By the way, your symptoms are classic, in particular, the fighting. That is not normal and such in-home brutality is rare…except among littermates, and especially same-gendered ones.

  9. johanna says:

    About 14 years ago I brought home a lab mix puppy and then a week later I brought home her litter mate. Both females, lab and german shepard mix from an ‘oops’ mating. They had a great relationship, bonded well with their humans and were great pets. As puppies they were boredom chewers but that was about all. One passed away two years ago of cancer and the other is riding out her final years. They never exhibited aggression or any poor behaviors. At the time I had siblings that were 2 and 4 and they were also great with the kids. I now have two smaller high energy rescue dogs and the old lady is great with them as well. I guess we were SUPER lucky!!

    • There are definitely exceptions! The siblings from different litters would not fall into this category, by the way, since they were/are at different developmental stages.

    • Thank you for posting your response. Johanna. I, too, somehow lucked out with my two 12 year old Husky/Dalmatian sisters (also an oops, I am assuming, as they were found in a dumpster at 8 wks, when I promptly adopted them). They rarely fight, and when they do, it is over as quickly as it begins. With what I’ve seen out there among litter mates, Mr. Stalling’s article is on the money. Johanna, you and I can count our blessings!

      The reason I want to thank you for your response is that I have the biggest fear that when one passes, the other will not be able to cope. The fact that you lost one two years ago (my sincerest condolences) yet the sister has thrived for since is soothing to me. I really needed to read that; thank you for giving me hope.

  10. Sue says:

    Sorry that your going through this with your pets. I was not aware of any of this. Hhowever i have to say that my neice adopted brother sister litter mates. They have had no problems except with mischief. Sister can be , but not always protective of her brother. They even go to dog parks and do very well. As far as bonding to their humans. With these two they love everyone. So happy story here but it sounds like its an exception to the rule.

  11. Deborah Bean says:

    We have been raising litter mates together for forty years. We have never experienced any of these problems. Seems these are problems of dog owners failing to maintain control of their dogs through training and less of raising litter mates together.


    • There are definitely genetic and training issue that can lead to this problem. It sounds like you are on top of both, so that’s great. But this is a real set of symptoms in many littermates. Read some of the other responses below. I delve into this more and interview behavior experts in an upcoming print expansion of this article. Thanks for your perspective, it is appreciated.

    • Steve says:

      Definitely agree, Deb. We have sibling standard poodles that were 3 in Jan and have had no issues. It is wise to spend quality time separately with each, but why wouldn’t you. Once one understands that “puppy class” is for owners, most of the rest is common sense.

  12. Chris says:

    I guess we got extremely lucky. We have two shep x littermates, both very very bonded, love each other, love us more and are the most social and affectionate dogs you’ll ever meet. They are sweet to everybody. They’ve never had a fight, are great with food and toys, love to chase but don’t get aggressive. They do compete for attention for sure, but never in an aggressive or harsh way. And we have a challenge with jumping on guests because they’re excited, but that’s as bad as it gets. They will be two in April, and have never had a fight or even exchanged harsh “words”. I’m knocking on wood as I type this….but so far, its the best decision we’ve ever made. I also have friends who adopted littermates a few years back, and they get along well too.

    • This is not universal among all co-homed siblings. However, it occurs frequently enough. I mostly want people to be aware of it, to avoid adopting siblings if possible (there are other reasons to just have one puppy at a time), and to know what to look for. It sounds like you have an awesome set of lucky dogs!

  13. Sandi says:

    I heard of this syndrome only after I adopted two female border collies at approximately 6/7 months of age (they are now about 11 months). They were found together and were assumed to be of the same age and litter. I adopted them separately but within about 6 weeks of each other. We brought them into a home with an 11 y/o male border collie we have had since he was 1 and a half years old. After a little bit of adjustment and my male bc assuring one of the girls that he was Alpha, the issues have subsided. They all play fairly well together or one-on-one but occasionally it gets a little out of hand and there is growling and mouthing but so far no blood. A squirt of water and separating usually does the trick. My question is, if we are fortunate enough to not have a problem by the time they are out of the puppy stage and are sufficiently socialized, what is the likely-hood that we are in the clear? We love these pups and I dread the thought that I would have to rehome one of them.

    • It sounds like your male may be a stabilizing force, so I wouldn’t think you have to worry about having to re-home one. You didn’t have them during the socialization period (up to about 16 weeks) so it’s impossible to know what sort of exposure they had to people and dogs. I would suggest that our spend time with each of the siblings one-on-one, focusing on separate training sessions with each.

  14. Bonnie B says:

    I believe it has more to do with trying to raise two puppies at one time. The same as any two children at oane tiem. it is far more difficult.It isnt impossible ant there are positive as wellas negative effects. But Two puppies at once can never getas much attention as one at a time

    • You got the “far more difficult” part right. Notice I said in the article that it can be done, but to do it right requires separate crates in separate rooms, separate training, feeding, walks, socialization, trips to the vet, etc. I was talking to renown dog trainer/veterinarian Dr. Ian Dunbar about this recently and he agreed strongly that there are no good reasons to do this. Yes, they may both turn out to be confident, well-adjusted dogs. But they may also be emotionally damaged for life. My point is, it’s not worth the risk.

  15. JT says:

    Interesting article and as a breeder I would not allow 2 to go to the same home, however I am keeping 2 from my current litter so will certainly watch out for these signs. However I would not take by babies out socialising until they are fully vaccinated at 12 weeks old

    • Waiting until after the 3rd set of shots is not in the interest of your puppies! Indoor puppy socials with non-littermates is the most important thing you can do, starting after the first set of shots plus 7 days. Breeders and new owners are doing a great disservice to these animals by waiting until AFTER the primary socialization period to introduce their puppies to the world. The chances of raising a dog with severe behavior problems far outweighs the chances of contracting Canine Parvovirus. They absolutely should be kept away from porous surfaces, including dog parks and beaches. But indoor puppy socials and meeting 100 people before 12 weeks old is imperative.

      The American Veterinary Society of Animal Behavior (AVSAB) concurs with this practice. Their official statement on the subject reads:

      The primarily and most important time for puppy socialization is the first three months of life. During this time puppies should be exposed to as many new people, animals, stimuli and environments as can be achieved safely and without causing over-stimulation manifested as excessive fear, withdrawal or avoidance behavior. For this reason, the American Veterinary Society of Animal Behavior believes that it should be the standard of care for puppies to receive such socialization before they are fully vaccinated.

      • Sharon says:

        Have you been through parvo treatment and the heartbreak of losing puppies? I have, not fun. A good breeder does puppy socialization with many different people, offers various stimuli, etc. To risk the health of a puppy with only one parvo shot just to socialize with other dogs is not a risk I would take or recommend. Been there, done that.

      • I have seen parvo. You’re right: it’s horrible. I also work in shelters with dogs with extreme fear because they weren’t properly exposed to other puppies and to people before 12/16 weeks of age. Many are needlessly extremely emotionally damaged. You can socialize your puppy very little risk of parvo if you’re smart about it. I attended a symposium on the subject at the University of California/Davis last weekend, a room full of veterinarians and veterinarian behaviorists. Conclusion: The risk of a dog being euthanized due to behavior issues resulting from a lack of early socialization is orders of magnitude higher than contracting parvo. This is not MY view; it is the official view of the most knowledgeable scientist in the field. The American Veterinary Society of Animal Behavior (AVSAB) official statement on the subject:

        “The primarily and most important time for puppy socialization is the first three months of life. During this time puppies should be exposed to as many new people, animals, stimuli and environments as can be achieved safely and without causing over-stimulation manifested as excessive fear, withdrawal or avoidance behavior. For this reason, the American Veterinary Society of Animal Behavior believes that it should be the standard of care for puppies to receive such socialization before they are fully vaccinated.”

  16. This looks like a really good argument in favor of the very early socialization protocol – handling puppies and exposing them to minute amounts of stress starting a few days after birth. There are breeders out there doing this, and describe the differences in confidence and adjustment to the human environment as nothing short of amazing. I’m very excited to read your expanded post!

  17. Sheila Babcock says:

    I will attest to what you are saying. I adopted out 2 boxer mix puppies, male and female. They came back to me at a year of age because they were so aggressive to people. Those 2 dogs attacked any animal in their paths. I kept them in fear of them hurting any other animal in someone else’ care. About a year ago, I had to give up my rescue and was terrified about these dogs. An amazing rescue took them and after being together for 8 years, they separated them. Those 2 dogs live amazing lives…..with other animals!! The two together were NOT a good idea, even though they were so bonded. It about caused them to lose their lives too soon. I also had a father son combo. The son was terrified of people. The puppy at over a year old got tick paralysis, and I had to take the puppy from the dad… thing that ever happened to that dog! He came out of his shell and is the most amazing dog! Thank you for your article.

  18. Marlene Johnson says:

    I raised 4 littermates, I had them since birth because I am their breeder, I did all the things you said, take them separately to the vet, to training classes, walks etc. They do not have littermate syndrome, they are 6 years old now, I still take them for separate walks etc. It really wasn’t all that difficult to raise them that way, but then I was aware of it from the start and did things accordingly.

    • Exactly. You allowed them to develop individual identities with the separate walks, training, etc. Littermate syndrome is not a foregone conclusion, but if you have siblings, you have to be diligent as you were to avoid it. Kudos!

  19. ThePayferPack says:

    Reblogged this on Payfer Pack and commented:
    Here is a great post, with an expanded article to come, by Jeff Stallings, CPDT-KA about why raising litter-mates is not in anyone’s best interest. While it can be done, if done properly, it is a lot more work and two puppies will not receive as much attention as one puppy would and to do it right, you need a lot of extra time and money. Thank you Jeff for writing such a great article! I will do my best to help spread it around.

  20. Mary says:

    As a breeder I completely agree with your comments on homing siblings or puppies of a similar age together. I think a gap of about 12 – 18 months or later is acceptable. Having said that, I recently kept two pups (both bitches) from the same litter. I made a tremendous effort up to about 4 / 5 months to separate them during the day. My usual routine was to send one of the pups to day-care and have one with me (I work from home). The one pup was a little more timid but having said that both have blossomed. They both are shown. They can be shown in the same class and focus on their handler, they can also go to a show alone without a problem. My only concern is that they play very very rough! I have never seen anything that would make me think that this could escalate to a fight but realise this is not impossible. They are now 18 months old. They also differ quite a bit in temperament. The one is a very outgoing girl and will go and play with everyone on the beach; the other is also playful but does not wonder off to play with other people on the beach but prefers to stay with us. The one is quite vocal, the other hardly ever barks, the one is destructive (will destroy toys or shoes if she gets a chance) the other doesn’t and the one will jump our fences the other won’t. BTW these are Golden Retrievers. Also I have a few adult dogs to which they are exposed to all the time. I think this also helps with what is acceptable behaviour and what not. Would love your comments about whether you think there might problems with them in future or do you think that we are on the right track?

    • You did all the right things as far as allowing each to spend time without the other. That is key. If you can do that, you’ll probably raise confident dogs okay on their own. It’s impossible to say whether problems will develop as they reach social maturity (about 3 years). Just keep focusing on having them be together sometimes and apart others.

  21. Jolene says:

    We have 2 brothers that are beagles and both of them have done well with other dogs and humans. They are best friends with each other.

  22. Paul says:

    We have kept 3 sets of siblings over the years, with no issues whatsoever. Temperament of the dogs and common sense of the owners plays a big part in how the dogs mature into adults. We have also also had several adults with the puppies which teaches them how to be acceptable members of the pack.

  23. Jules says:

    We used the “very early socialization protocol” on our litter of 6 pups 4 years ago. We did not let puppies go to their new homes until fully socialized at 12 weeks. We kept one pup. We have recently gotten one of the pups back due to a family problem and noticed that although the dog received no formal training, he is well mannered, sociable, gets along well with his littermate who is here, re-integrated with no fuss or bother and has no fears or phobias (i.e., fireworks, vacuums, etc). The owners of the rest of the pups attest to their stable temperaments.

  24. Liz Hogg says:

    We rescued two female shep X’s and were told from the very start to watch out for the hyper bonding. They are now almost 4 years old and I can I can honestly say we really have not had any issues. We have had the occasional, though very rare fight, they play well together and love other dogs. They are very affectionate with us (one is almost too loving!) the biggest problem we had was teaching them their names (though once we got some advice we solved that in one afternoon with a whole lot of treats!) I find they are no more upset to be apart then my past dogs who were not siblings. Overall it has been a great experience though I would not do it again because it is a lot if work (though I still believe that dogs should always have a friend) early socialization was the key I believe.

  25. Patti says:

    We have 2 lab mix littermates that we adopted 3 years ago when they were 4 months old. We had never heard of nor did anyone ever tell us about Littermated Syndrome. In fact, the rescue we adopted them from was so thrilled that we were keeping them together. As a result we did everything with them together (from crating to training to vet visits and so on). I will admit that sometimes they function as “one unit” but they are very well socialized and each has her own individual personality. I will however take a page from your book and begin working them separately. Hopefully it’s not too late! Thank you for a very interesting and informative article.

  26. Dave says:

    I think that this also apply to kittens, I can now understand why my two are like they are

  27. Mina says:

    This text was an eye-opener, everything now makes much more sense and I think I finally got an answer to question I’ve been asking myself for more then two years: “Why is my dog like that?”

    I must say my experience …. I got a female Dobermann puppy at age of almost 7 months, which stayed with her breeder until that time … She had one litter-mate staying there with her and other dogs similar to her age … I know for sure that they were always together, meaning breeder didn’t feed them separately, take them to walk separately etc …
    When I got her, I experience the most disturbing dog personality I have ever ever encounter. Such amount of fear was unbelievable! And it wasn’t a fear that she would easily shake off or get used to quick…. It was so intense and so irrational, completely without any logical understanding or explanation. She feared everything that was around her, inside and outside of house. Passing through doors, stairways, bags, bushes, trash cans, traffic signs, not to mention people, dog, traffic or noises, she feared going outside when it’s dark, or passing over bridges, under highpasses etc … everything! To her I was OK, but I with a cup in my hand was not. It was the most horrible experience of my life. And every time I talked to her breeder, she told me that in her pack she was just fine, not scared and being even bold and outgoing! The breeder thought it was my fault …
    I struggled with her for many months, thought that she is just poor socialized and spent up to five-six hours every day (before and after a full-time job) to get her accustom on as much as possible things that was going outside, and also inside, and after couple of months of endless hours spent with her, I finally get to see glimpse of improvement. We continued hard work, and socialization and education, and now with her being almost 3 years old, I can say she is doing much better, most of the time you can’t even say she is fearful or shy or was anything like before. She has well manners and is very obedient, has very strong bond with me, and is very much loving to anyone she knows, dog or human. But is still shy to most strangers, especially the ones we meet outside, very rarely allows strangers to pet her, and doesn’t like to play much with dogs, only ones she knows; and also it takes much longer to get her used to new situations or items … Like she was fine with metal crate in the house, but it took me three weeks to get her accustom to plastic crate inside a car, and also I’m trying to get her accustom to dog trailer (for my bike) but very very slowly, so it’s taking now more then couple of months …. So, in the end, thankfully we worked it out somehow, she is manageable and loving, but I know she will always be “my special one”, and I’ve except her as she is.

    Thank you for this article,

  28. Bonnie says:

    Come to my house and see the exceptions to the rule!!

  29. Gewanna Nichols says:

    I have adopted a brother and sister from the same litter twice. First, a pair of Jack Russell/Beagle mix and then a pair of Dobermans. I haven’t seen these extremes in my pairs and we were always pleased about having a pair so they weren’t alone. Now I have one old Doberman and a Mini Dachshund. We adopted the pairs at 8 weeks. The only aggression was between the girls and boys of the different breeds. It always seemed to be the Alpha battle.

  30. Bridget says:

    It’s funny that most of the responses completely agree with the author. I have three litter mates, 2 boys and a girl, and not only was it not hard to socialize them with other dogs, or take them to the vet at different times, it’s also quite easy to feed them in their crates and play and work with them or walk them individually at different times. None of my three show any of the “syndrome” mentioned in the article. I think the article is very one-sided as it doesn’t cover what may have happened during the important time period when puppies get introduced to strangers and strange noises, a time when they are within their litter protected by Mom. By the time my pups went to their homes, they were used to normal household noises and had seen plenty of other humans as well as a couple of other dogs. Even with my three now, I do not have any of the listed problems aside from normal age appropriate squabbles.

    • I am sorry you find the article one-sided. In fact, you mention the manner in which you worked with your dogs (walked, crated, played and train separately) is exactly what I recommend for siblings in the article. This absolutely is a socialization issue, with the siblings not properly introduced to strangers, other puppies, noises, bicycles, cars, buses, children, etc before 12 – 16 weeks because of the hyper focus on each other. Also, as for the alleged one-sidedness, I do state that there are exceptions. I don’t have the resources to do a bona fide study. The upcoming print version of this article expands on this a great deal, and I interviewed Dr. Ian Dunbar and renown behaviorist Nicole Wilde as well, both of whom have dealt with numerous tragic cases. So, just because you took the appropriate steps to individually socialize and train your siblings doesn’t mean everyone else knows to do that, or even how. That is the purpose of the article!

  31. Kevin says:

    I have two rescues from the same litter who exhibit none of these problems. They have only been separated from each other one time, the day they were both neutered. From the time I got them I socialized them heavily with other dogs, people, and other animals. They’re now over two years old and are some of the best behaved and socialized dogs I’ve ever had.

  32. Elisabeth says:

    I am a breeder and have experienced this when running on two bitches. Invariably one would turn out ok and one would not want to hook on and work properly with me, the one not hooking on was always desperate to scale authority in the pack, not just with the sibling, so I feel its an alpha issue. Always trained and fed separately, taken for drives seperately, seperate shows etc. Never had a problem running on a promising bitch and dog from a litter… but again a lot LOT of work of separate training and social activities. I am lucky my extended canine family are all obedience trained and help to pull young dogs in line, we work as a pack, Running on siblings is not easy and I fully dont recommend it to the average dog owner. Lots of sweat and tears.

  33. Fred Neal says:

    My personal experience is quite the opposite. I’ve have/had two sets of female litter mate Mastiffs, and at the same time. No problems at all! They always had someone their own age/size to play with. Just need to always treat them equally. I learned to use there names first on commands and reprimands.

    I pretty much violated all the rules you list. They were raised together. Fed together (separate bowls). Slept together. Went on outings and to the vet together. I do spend some individual time, but mostly we do things as a pack (currently 7). Some puppy training required one on one time. I do require a structured environment and required all to mind. I believe discipline is a must, especially when dealing with giants. That is not meant to say I use negative, cruel or abusive training methods.

    Later, as adults, they all are very social and have helped many rescued fosters de-stress, relax and recover. They are, and always have been, very social to dogs and humans. Now as seniors they still snuggle, do everything together and are best friends. It is great to experience the special bond litter mates have for each other.

    The worst experience was when I lost one. The pack did mourn, especially the lost’s litter mate, but everyone did move on.

    Even the two different sets liked each other, but not as much as their own sibling. Perhaps the generally mellow Mastiff temperament is a factor. There are always exceptions, but I certainly would not hesitate again to bring in litter mates when the time arises.

    • The article notes exceptions. But read through some of the other comments on here. It’s a real phenomenon.

      • The fact that they spent lots of time apart between 8 weeks and 6 months could be a huge factor; they had plenty of time to develop their own personalities and experience the world without their sibling. This is key. There is a strong genetic component as well, and your giants may not be predisposed to it. Plus you obviously know what you’re doing! Thanks for your perspective.

      • Fred Neal says:

        I’ve no doubt it does happen. However, there may be more to it then just being litter mates. I know some that swear multiple dogs of X breed have problems with each other even when introduced as unrelated adults. Sometimes males, sometimes females. Sometimes rescues need to be the only dog. They are all individuals.

        Not sure about the second comment spending lots of time apart, mine have always been together. Maybe it was intended to be in response to a different comment.

  34. Belinda says:

    Four and a half years ago we brought home two female Beagle puppies. They started fighting the day after we got them and it just escalated from there. No one warned us about the problems we would encounter such as them failing to pay attention to us and only focussing on each other and it was only after searching the internet that we became aware of this syndrome. We persevered for 6 months, training, feeding and walking them separately but the fighting escalated until they were hurting each other (and us when we tried to break up the altercations). It got to the point where I couldn’t go to work because I had to keep them separate. We eventually had to rehome one of them with a friend and they have both been calm, happy and well-adjusted dogs ever since.

  35. Julie says:

    I am not seeing this. We have giant schnauzer littermates that will be two years old the end of January. They are male and female. We have had the female since she was eight weeks old and the male off and on after that but at about six months he came to us permanently. She is very alpha so we started socializing her heavily as soon as she had her third puppy shot. At eight months of age she started basic agility and attended a puppy class. After he arrived, we did not socialize him as much but he has now also started in agility classes and has been to a carting demo. She has done lure coursing and herding. She is far more mature than he is, but I think that is somewhat the nature of male and female giants. They were not neutered until they were almost 19 months of age to allow their bones to fully mature. We do have other giant schnauzers that they play with. Two other females who do mother them and keep them in line when needed so it is not just the two of them. We have other male dogs that the female of the litter plays with. He is very OCD about chasing balls and toys and retrieving. I also do giant schnauzer rescue and we have taken in and adopted out several pairs of littermates. One was a pair of male giants. We don’t like for people to have same sex giants unless they are very familiar with the breed and know how to handle them.

  36. Genie Murphy says:

    To respond to the comments about breeders and rescue groups encouraging people to adopt or buy litter mates, responsible breeders do not sell litter mates to a buyer for the very reason explained in this article. I have bred dogs in the past and refused to sell litter mates to buyers especially if they were unexperienced dog owners. I will interview and investigate the buyers, check references, and get to know the people and their experience with dogs and the breed in question and based on the outcome of the investigation would then decide whether or not I would sell them litter mates. However, a general rule of thumb is to refuse to sell litter mates to inexperienced owners. Responsible breeders do know about how difficult it is to raise two dogs of the same age be they litter mates of from different litters. Obviously, the woman who bought two “chiapoos” did not buy from a responsible breeder as a “chiapoo” is not a breed, they are mongrels and the “breeder” was only breeding these dogs to make money and cared nothing about the dogs.

    • Liz says:

      If the buyer had other dogs or enough people to work the dogs and give them time I would. I am a responsible breeder.

      • Older established dogs in the household seems to be a mitigating factor. Enough hands on deck to give each and every puppy born a rich socialization, whether littermates or not, and the problem would all but disappear.

  37. Anne Wilson says:

    Loved your article. Did not know of these problems with litter mates and the rescue encouraged us to adopt both the six month old cocker spaniel/silky terrier sisters together. They are now two and a half years old and very happy dogs, good with children and other dogs, although one is more timid. I did have problems with training and walking properly on a lead. Puppy school was a disaster and they had to be taken separately. I’ve not seen any aggression towards each other and they play well. They sleep together but are happy to be apart when inside. The timid girl is much more people oriented and happier to spend time with me rather than her sister and she was easier to train. I am so happy we don’t have any major troubles as they are both adorable. Thank you for all the information – I also really enjoyed reading the responses and comments.

  38. lori says:

    Interesting and informative article….unfortunately for the dogs, one, two, three or however many dogs people decide to raise(train)??? is all about how they train(raise) them….just like human children; if you don’t discipline and train them, they will grow up to be problems…i have raised(trained) many sibling puppies and it takes A LOT of energy, just like raising children, of which I raised three. It is ALL about how you deal with them, whether you let them be the alpha or you are the alpha…….all human babies and canine babies are trainable.

  39. fibait says:

    As a serious small breeder of quality purebred terriers, I have always refused to sell littermates to prospective buyers. A single puppy of our breed is sufficiently challenging to even the most knowledgeable owner!
    I also require that the pups leave my home at 8 weeks, the most favorable bonding age. Recently, I made an exception for a buyer who wanted a pick bitch at age 12 weeks, so I kept the 2 best bitches much longer than I had ever done before. They formed a mini-pack and caused me concern. Now that one has left, the damage does not appear to be lasting. My little bitch and her littermate are thriving in their separate lives. But I will never do that again!
    Thank you for spelling it out. I will send this article to any future buyers who are asking for littermates or who want a pup older than 8-10 weeks.

  40. Mari Lynn says:

    My ex husband and I fostered 2 beagle mixes in the early 1990′s from a local rescue. The puppies were around 3 weeks old and the mom had been hit by a car. By the time they were old enough to be adopted by the agency, I couldn’t let them go. We did have littermate issues but they were very mild and mostly funny; we’d give them both a toy and they would chew, cuddle, within inches from each other and growl, grumble, glare(guarding). if we moved them and the toy to a distance apart they didn’t like it and would return to ‘inches’ apart and continue cussing each other out. We didn’t do the socialization we should have because we didn’t know about it. They were happy, reasonably well adjusted, well trained although in a 2-dogs-1-brain sort of way, and accepted other dogs, cats and people. Years later when they were around 9 or 10, fighting started, infrequent still, but it was always the same dog getting hurt, once ending requiring stitches and in a serious infection that didn’t heal easily. We had to be much more watchful and never quite figured out what caused it. Could it still have been a late arrival of the more violent part of the fighting littermate syndrome that had only exhibited as grumbling? We were fortunate with them but I would never do a littermate adoption again. I’m a part time dog trainer now and really try to advise against it when I can. Great post and comments. Thank you.

  41. CL says:

    I had a pair of sibling labs in one of my classes, and one week the female came to class with sutures over her one eye, and when I asked what happened the owners told me that the male had bitten her when he was stealing her food. They also mentioned that the female will crouch over her food and eat quickly. I recommended that they feed the dogs separately. The male owner basically told me that they were his dogs and he would do what he wanted with them, and my suggestion was dumb and the dogs would “figure it out.” One week only the male was in class, and he almost couldn’t function because the female wasn’t there. I also warned them that letting the dogs “figure it out” would probably esclate and they would end up with major vet bills. Unfortunately they all unexpectantly stopped coming to class, or communicating with me at all, so I really hope nothing too terrible has happened to the dogs. I have recently started talking about Littermate Syndrome in some of the classes that I teach, mostly the puppy class when sibling puppies (who are owned by different families, luckily) are in class, we highly encourage the pups to interact with the other puppies, not just each other.

  42. Mary Ann Rose says:

    I have raised sibling Scottish deerhounds, one sib set at a time, for over thirty years. I have never had the problems you mention, but it was likely because I was told very early on by a reputable trainer that it was important to separate the siblings for eating/sleeping/ training experiences early on, as you recommend. Most reputable deerhound breeders do not hesitate to sell siblings to experienced owners, especially those who like to show, course and hunt–the reason? Because with the giant running hounds, it is nearly IMPOSSIBLE for an owner to give the puppy the degree and the KIND of exercise they need to fully develop into a functional sighthound. If you are writing an article to be widely published, you should talk to a few deerhound/wolfhound/greyhound breeders.

    • Michelle Cowan DVM says:

      Most Deerhound breeders also keep their puppies until they are at least 12 weeks of age. Raising puppies in a pack situation, keeping them with sibs until this age makes a huge difference in their responses to the outside world. I have no problem selling pairs of sibs to experienced people. As Mary Ann says these dogs need a huge amount of exercise as puppies and it needs to be on their terms not on a humans.

    • Joy Windle says:

      I’ve lived with sighthounds (Borzoi, Scottish deerhounds & Whippets) for 35 years. With the large breeds, it’s much easier to grow them out well if they have a playmate of the same size & style. In one case it was a borzoi & a deerhound bitch, born a day apart in different states which came home together at 10 weeks. Currently, 3 year old dog & bitch Borzoi litter mates are the household youngsters. Although they slept together in the same ex-pen as little puppies, they ate sedately from the beginning, tho’ not in crates or separate rooms. They continue to go to classes separately, and they frequently show on different dates to different judges. When Phoebe is in season, Eddy goes to camp. They do not quarrel, but Eddy is very much “me-me!” and will push his smaller sister aside if he can. As the owner, it is my job to make him mind his manners and wait his turn for attention. They are both clearly bonded to me as well as each other & the senior dogs in the pack, but they don’t freak out if I hand a lead to someone else if I need to step away for whatever reason. I am not unique among Borzoi breeders & owners in this.

  43. Norma Braun says:

    I am a breeder and show my dogs. I usually keep one to two puppies out of a litter for showing and I have not had any of these issues. Of course, I socialize quite a bit and the puppies are taken to show matches separately and together. I have never had this problem with litter mates. I can see how a “pet” person who doesn’t show or train their dogs for some type of performance event may have a problem but I haven’t had this. I have only sold litter mates once and they turned out beautifully and the owners did not have any problems. However, I should note none of my puppies leave the house until they are almost four months old. The breed is Norwich Terriers. I do believe socializing is the biggest responsibility we have as breeders of any breed.

  44. len says:

    Thank you for such a good article. I was a foster failure and kept two litter mates. I got them when they were four weeks old. One male one female. I talked to a well respected trainer locally and the first thing she told me was to take them separately anywhere several times a week. It was a monumental task but I took one to the park then one to the store and the saga goes. They will be four in July 2014 and they have different sports. I trial with the female in agility and the male is a therapy dog and trials in rally. I have just this month started to take them both to the trials of each other. QUESTION: is this a mistake?
    They play hard together and run like the wind ( they are flat coat retrievers) they have acres to run on but you can see they always keep their eyes on each other and sometimes the play is rough, but they always settle into their “preferred corners” in the house.

    • Heck no, no mistake there. Man, those pups are lucky to have you: One does agility, the other therapy and rally. Once again, a focus on giving them separate identities and ample opportunities to understand the world, people and dogs and you can end up with co-homed dogs as functional as any two dogs, siblings or not. The article points this out. That said, it’s impossible for most people to do. Your dogs are lucky, and it sounds like your are too! Kudos!

  45. Becki says:

    I have 2 Saints that are litter mates. However we did not rescue one until they were 10 months of age. We rescued him from a home where he was inadequately cared for, never socialized and needed vet care badly. Both were great and didn’t show any of the symptoms until this past April when they were about 18 months of age. Max ( the rescue) barks and lunges out of fear at other dogs and people. He is great with my family but no one else. Moose whom we’ve had since age of 11 weeks is laid back and loves everyone and everything.

  46. Rachael says:

    We just adopted littermates three days ago,10 week old girl and boy great pyrenees and shep x. We had no idea of this problem. If we split them for six months do you think this will prevent the problem?

  47. Diane says:

    We have a brother and sister littermates…the male we got when he was 7 weeks old but did not get the female until they were 7 months old.. Although we are convinced they knew they were littermates even after being seperated we have had nothing but great experiences with them. They are very attached to each other but love to interact with everyone, including other dogs (we have 2 cats in the house also). Our primary concern is how they will adapt if something should happen health wise to the other…it will be a great loss for all of us!

    • They were not together during the developmental stages that would have caused problems. It’s not that they are siblings, but if they are littermates who are never apart. All dogs who live together grieve, that’s normal. Sad, but normal.

  48. Jennifer says:

    We got our two Alsation x Collies from a shelter and not only are they littermates (2 of 11), they are bitches and they were orphans who were not put with a surrogate. We now know they received no mothering discipline and that same sex siblings can show greater rivalry. We had disastrous time at puppy classes so stopped going and have trained Bess and Abbi separately with good results, managing to train to voice and hand signals. Although house training has been very difficult with both pups clearing each other’s messes and although 99% of the time our house no longer stinks is not fully implemented yet (they are now 6mths old). We feed and play them together but always put the dominant one first, maintaining what we perceive as the natural hierarchy. We walk them separately as it is virtually impossible to go out together however the one left behind becomes very agitated – whining, pacing and scratching the door, especially the dominant one. This is when they get 1-1 play and training time in an attempt to distract and reinforce/strengthen the bond with us. The only time we all go out is to the beach. So far so good (I hope) the only other syndrome we haven’t been able to curtail is the fighting. As yet this is not overly aggressive and we intervene with a distraction noise (verbal “ac-ac”). We trust this would be alleviated once they have been spayed?
    My husband and I are not young and not in rude health, everyone has advised us to re-home the dominant one for the pups’ mental stability and also for our sake but we are loathe to do so. Beautiful Bouncing Bess and Abigail Dolores Malone have wonderful temperaments and great with our grandchildren just crazy together.
    Does anyone have any other advice or suggestions? Is it just a question of a bit more time, patience and several boxes of tissues?

    • My main question, beyond why you are keeping both pups when they are showing all the symptoms of the syndrome, is why you are waiting to spay them? Make an appointment today. This may not change their behavior now, but it will save you lots of problems down the road. Littermates with symptoms in heat would be a nightmare. It sounds like you’re making the best of a bad situation, but not one I would intentionally enter. That they had no maternal direction make it even tougher. You’re a trooper for moving forward and I wish you the best.

      • Jennifer says:

        Thanks for your good wishes, spaying booked. Have searched out other owners of littermates locally, the support and extra advice to try different ideas has been wonderful (just knowing we’re not alone in wanting to keep our girls is keeping us sane). Also got a “dog-whisperer” on board with experience of the syndrome. Turns out that whilst life is more difficult and at times stressful our situation is not unredeemable.
        From experience so far my advice for anyone wanting 2 dogs would be to get one puppy at a time with at least 6 months in between, However if 2 at once is the commitment then get yourself armed with as much info as possible from both sides of the argument and ask your local vets/pet shops/breeders for a recommended trainer with litter syndrome experience willing to come to your house. Knowing what you’re letting yourself in for is half the battle. Of course, dogs all have differing personalities and keeping littermates does not always work out but at least you will have the knowledge that you tried everything you could.
        It has only been a week since tearing my hair out and feeling like the worst dog owner ever to knowing that there is light at the end of the tunnel. Having outside help is key and asking for assistance is not a sign of weakness or inability to cope – it takes a strong person to stand up and admit to needing someone else.
        Good luck.

  49. Cherish says:

    This is very interesting and I had no idea. Thank you so much for the article!

    I was wondering, can this syndrome exist for puppies that are not raised together, but are siblings and raised in the same family. In my specific case, (and this was years ago) my brother’s dog had puppies. He kept one and I took another (the rest were given to good homes and we never saw them again.) At first we would socialize our pups together and they were fine. However, after they were a couple of years old, they were very antagonistic towards each other. We never brought them together again main because my brother’s dog (who was bigger) would growl and snap at my dog. I’m wondering if this is littermate syndrome. This is just for my information, as my family is close and we often visit with each other & bring our dogs with us and I would never want this to happen again. Both of the dogs described above are now gone (it really was years ago) and all the dogs we have now all were adopted from different shelters and came from different litters.

    Thanks for your time!

  50. Chell says:

    I am getting an 8 week old choc girl and 9 week black girl lab from 2 different litters. I had planned to do separate kennels and training and LOTS of socializing. Glad I read your article. Any advice greatly appreciated

  51. Chris says:

    Thank you for this information. I have been running a puppy rescue for 10 years and people get so mad at me when I refuse to adopt litter mates or 2 puppies together. I am thrilled to have something in writing to back what I am saying to them.

  52. Izzbizz says:

    So true. I’ve been saying this for ever, how annoyed would you become if you had to live with your siblings during adolescence the rest of your lives. Pissed. Lol. Overwhelmed. It’s so true, when they have each other from such a young age, and then no educated guidance or leadership on the dog owner or dog lover, usually, in this case. They become so enthralled in each other. They never spend time apart. They become this intense tight knit unit that is a very primal pack almost, where they know human is not leader. My only question would be, could this happen, adopting two pups in the same development stage, different litters, or breeds. But one tending to be a companion breed, she now latches on, in many of the described ways, aside from the extreme dominance, but it does happen? Or would that just be a simple dysfunctional pair. Because one has no confidence without the other, the other doesn’t notice the other leave. Two clients of mine. The weener dog had a bulldog sister, both puppies, grew up together, then suddenly bulldog passed away. Then they got another for her the weenie, and now she’s just completely lost without her siblings, the other has no issues, but also has more confidence. Very neat how dynamics develop without a structured eyeball watching lol

  53. Hi Jeff,
    My two older huskies (who were not fixed at the time) had a litter. Originally my boyfriend and I had intended on keeping just one puppy, but after falling in love with the runt of the litter, my boyfriend and I decided to keep two. They are fantastic play mates (only 9 weeks old) and my two older huskies are fantastic with them. I have been noticing that when outside together, they dont seem to listen to the humans, and when in the house they are more focused on each other and their toys, instead of playing with us. My boyfriend and I are in this for the long haul and are prepared (and recently have been) keeping them separated, feeding, playing, walking, socializing, and training solo. Is there anything more we can be doing, or any advice that you could send my way? Id really hate to get rid of one of the puppies as we adore them, but of course want whats best for them.



    • Having older dogs in the picture seems to reduce the chances or severity of the problems. Just make sure they get lots of quality time apart. I am not sure where you live but if you have access to puppy socials, take each separately to 7-10 before 18 weeks so they each get a chance to learn the nuances of dog language from pups other than their siblings.

  54. Thanks for the advice! Just another question, Ive noticed that they’re already becoming very attached to one another, and not responding to or bonding to my boyfriend and I. Friends of mine have offered to “foster” one of the puppies for a month or so just so they can have some separation, do you think this would be beneficial?

  55. I have two 8 month old Jackapats a boy and girl. and after reading some articles became worried of what they may grow to be like. Luckily so far, all’s good! when they start to become sick of one another we simply separate out their activities one does training and the other goes walking and when greeting other dogs we have found their bouncy energy can be very overwhelming for other dogs so they greet separately and calmly. They have had no problem bonding with humans and rather curl up with us than each other. Their success may be due to the fact they are polar opposites the girl bold and brave, though is submissive to the taller loving lanky wimp, her brother. both have been neutered and spayed, so fingers crossed their will be no problems in our household.

  56. Olga Shmatkova says:

    Hi Jeff,
    more than two years ago, Oct.2011 to be exact, we adopted two 8 weeks old English Cocker Spaniel siblings from the same litter and I happen to read your article before we brought them home and I was terrified to the point when I called the breeder asking if it’s not too late to get just one puppy and she refused to refund us for the second puppy so we ended up taking them both. But I was prepared to deal with Puppy Syndrome and my girls started basic obedience training at the age of 12 weeks, were spayed before their first heat, were sleeping in the separate crates until they were one year old. Potty training wasn’t difficult at all, each of them have their own favorite human, they bonded to each other, but it’s nothing like you mentioned. They love people, excited when they meet a new dog, never fight!, great with sharing their food and toys, play with our grandchildren, who are 2 and 6 years old, do not show any signs of aggression at all! They don’t like to be separated but don’t get anxious when one is taken out. I can go on and on for hours… My point is – the owner must be aware of this Syndrome and be prepared to work twice as hard and, of course I think that human must be in charge and set strict rules when raising puppies.

  57. Pingback: Anonymous

  58. Kevin says:

    Hi, I wanted to just voice my experience. I have two blackmouth curs that I rescued at 5 months old, they were the last of a litter and both males, looking almost identicle. As they are hunting dogs I expected some agression but it got very bad at times. Having raised them with my girlfriend thru the latter portion of college and now we are into our early careers, they have calmed down immensely with eachother and socialize very well with humans (dogs, not so much). We found some techniques that helped a lot – crating is a must and separate crates especially, we feed them separately as this was a trigger for most of their fighting at a young age, now there is little to no aggression with food of any sort (other than bones, they still get agressive with bones), we schooled one that seemed to be more agressive, the only one that would show agression toward me, and this helped a lot as well. side note: they are both fixed – a lot of agression went away after making this move. It’s now almost 4 years we have had them and it’s a great feeling to see the bond they have developed with one another but also with my girlfriend and me as well as each of our families. Our dogs have endless personality and I wouldn’t trade them for the world but it was A LOT of work, almost too much. I wouldn’t advise anyone to do it, and had I known before hand I may have not rescued both of them, but I can’t imagine a life without both of them in it. Anyhow this is a fantastic article and I feel for those people struggling with sibling dogs, but if you really love them and want to keep both as we did, (unless there is literally no hope in sight) stick with it and socialize, train, feed, crate, SEPARATELY and maybe they’ll start to come around as my boys did.

    Good luck and thanks for the write up.

    • Cherish says:

      My comment is not about your experience, other than to say thank you for sharing. When I saw that your experience is with Black Mouth Curs, I had to write share that my husband and I rescued a female Black Mouth Cur almost 2 years ago and she is such a joy! This was a breed with which I was completely unfamiliar and I’m so glad we took the plunge. They are such warm and loving animals. I would adopt another Black Mouth Cur in an instant.

      Thanks for sharing your story.

  59. Karen says:

    Thanks for this article, I had never heard of this syndrome. I’m about ready to adopt and was considering getting two, but now I’ll wait and get a second down the road. I’m kind of relieved, too, because I was dreading the chaos I was about to impose upon myself having two at once! Win-win!

    My dad got two at once, and some of the symptoms were there. They didn’t fight often, but when they did it was bad! When the bold one passed away prematurely, the shy one blossomed into a loyal and protective companion. We hadn’t realized how repressed she was until her sister wasn’t there to steal the show, so to speak. Even though she stopped barking at dog walkers passing by her fence, she remained unpredictably aggressive around other dogs. We didn’t see anything wrong with how they behaved, we just figured they were a pair, always a pair, although, I can remember feeling that they weren’t as close with family members as other dogs we’ve owned.

    The symptoms were mild, but I, personally, wouldn’t want to risk even mild symptoms! I want to give my girl all the advantages I can to help her develop into a well behaved lady. I’ll get one now and one later and maybe the older one can show the younger one the ropes.

  60. Pauline says:

    This is nothing to do with this subject I did find it very interested being a dog owner for over 45 years . Just a question my neighbour who has a female Husky who breeds her twice a year different breeds of dogs ( German Shepherd now Husky ) selling them as purebred pups I did not think this is proper I actually do t agree with breeding your dog for just the money side

  61. tina says:

    How Long would one have to seperate them for meaning training wise . We adopted two female pure bread boxers being unaware of all this like most people :( we got them yesterday we do however have two crates and are doing everything apart training , eating and play time . My question is how many weeks do we hve to do this before tey can be able to cuddle and spend time together ? Thank you

  62. kathy says:

    I have 2 male American bulldogs that are 61/2 months old(tank and pudge). I have had them since 8 weeks.I have a 10 year old male boxer and a 5 year old male bichon. They sleep in separate crates. and I walk them separately(only because they are 2 strong for me to take both 80 and 75 lbs.) Pudge is good on the leash tank is okay not great. He doesn’t like other dog but pudge is okay.
    when I noticed tank didn’t like other dogs at 4 months old I signed them up for doggie daycare. they did 2 weeks straight and were trained in basic commands. Tank took time but in a couple days the trainers said he was fine there. Plays with 50+ dogs on any given day. They recommend I try to take them 2x a week until adolescence. I had them neutered last week. They exhibit a fear of loud noises.and tank recently shows fear when my son’s friends(16 and 17years old) I tell the friends to ignore him and sit down until he comes to them. it has helped. he adjusts.
    I have always had 4 dogs at a time but never siblings.
    Do you have any other suggestions so they don’t develop into full blown syndrome?

  63. I have a rescue organization. I find that people will give up both ill behaved dogs rather than choose one to focus on. It seems we get pairs of sibling pups that have failed as pets frequently. I NEVER recommend adopting sibs together. When we acquire a litter of pups and someone wants two I won’t adopt two pups to them. I have seen too many situations where both dogs end up homeless. We see posts all the time where people are trying to keep sibling dogs together and I just think how misinformed they are. If you were in rescue and you continued to get these pets six months to twelve months old that are so untrained, you would never even think about adopting a sibling pair!

  64. Christine Gray says:

    Hi Jeff,

    We were just discussing this very topic last week. As a Animal Care Center employee and lead on the adoption team this questions comes up regularly. We discourage adopting two puppies from the same litter (but do not deny) and actually recommend waiting a few months before bringing the second puppy into the home. Usually after experiencing Puppy #1 they decide to wait much longer for Puppy #2. Thank you for providing me with an article I can share with staff so that they can reference why we suggest this.

  65. Because of a series of life circumstances, I have female littermates from a litter I fostered 3 1/2 years ago. I was/am very aware and knowledgeable about littermate syndrome. (I also have one older dog and one younger dog.) My family and I have worked (and continue to work) very diligently to offset littermate syndrome. Along with our other dogs, they sleep, crate, eat, go to classes, do therapy and crisis response work, compete, and have one-on-one time separately. They love their individual time and their family time. They are very well adjusted and stable dogs. They have both unique and similar loves and interests. But as I said, their lives and activities have been very planned. It is a great deal of work, but it is an act of both love and responsible pet ownership. Acquiring littermates is NOT something I recommend. But I will help and support those who want to do it and want to do it responsibly and lovingly.

  66. Mary Bird says:

    My first reaction was bull, until I read the article. We have rescued and adopted litter mates three times and would do it again. Never had a problem except two Shepard crosses who did show some aggression to each other but eventually sorted it out without any damage. More importantly, we have always had at least one other dog around when we brought in litter mates. Our experience has been that the training curve has not been steep as the new dog or dogs watch the older dogs and learn from them. I feel like we have not trained a dog in years because they learn so quickly from the older dogs and people always comment on how well trained they are. We also have the advantage of four adult humans in the house so there is seldom a time when there is not someone with the dogs and we all love dogs and interact with them all the time. I personally have never experienced the syndrome but it would appear that this is a result of our particular circumstance. For us it has not been an issue and have never found litter mates to be more work than single dogs. In fact, we have never found any dog to be work, including abused rescues. Love, patience, grooming, feeding, vetting, daily playing, walking and cuddle time are all pleasant and easy to do and will turn the most nervous, distrustful dog into a happy dog.

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