Littermate Syndrome


When you are thinking about bringing home a puppy, don’t be taken in by an extra pair of puppy eyes and bring home two. The problem with bringing home two puppies from the same litter is littermate syndrome, or even from different litters at the same time, is the strong possibility that they may at first bond only to each other (later there may be some strong dog on dog aggression often requiring dog behavior modification to help with the issues (especially with littermate syndrome – details to follow). When this happens, the two puppies who are strongly bonded could even exclude their owners.
Rottweiler puppy
Rottweiler puppy

What is littermate syndrome?

Littermate syndrome, for the most part which will be explained later, is when two siblings are adopted together, and they bond only with each other and no one else. Not their owner; not another dog, only to one another. The siblings will become overcome with anxiety if separated from each other. Then, as they mature, one or both of them can become extremely aggressive towards the other one.

Some of the signs of littermate syndrome can be when the dogs are afraid to be around other dogs. This is because the two siblings have bonded so firmly together that they don’t understand other interactions with other dogs. Other signs are:

• Fearful of stimuli which are unfamiliar

• If the siblings are separated, even for a short time, their level of anxiety rises to a high state.

• The puppies fail to learn even the most basic of commands because they are focused on each other.

• Difficulty in training the puppies because they are continually distracting one another.
Littermate syndrome doesn’t happen to all adopted siblings, but it does occur very often.

Fighting among littermates

The possibility of fighting between the siblings when adopted together is higher. Aggression and bullying is one of the most common complaints with the more dominant one intimidating the less aggressive one. This happens as the dogs start to reach maturity and squabbles and fights start to break out regularly.

So, what about neutering and spaying to help with this? If you have two male siblings, if you castrate both dogs, it can make things even worse. It’s because you have to neuter the less dominant male, when you castrate both, it changes nothing. This is because they will still fight about position, rank and dominance. If you neuter the less dominant male, it leaves room for status and position in the dog hierarchy for the top dog which the other dog will recognize.

If you have two females, when spayed, it can increase the level of aggression. Spaying removes the hormones, Oestrogen and Progesteroneste, which are calming hormones. Since these hormones are now missing, if the aggression levels rise, the female dogs could fight to the death if not kept separated.

Breaking up a dogfight

Breaking up two fighting dogs is dangerous to both you and your dogs. Don’t ever attempt to break up a fight by grabbing dog collars. If you try to grab a dog while they’re fighting, redirected aggression is very likely to happen. This is where you are most likely to get bitten and sometimes bitten badly. One of your dogs may think that you’re part of the fight and act accordingly. A dog may also redirect to and bite the owner to free themselves up to get to the percieved threat (the other dog) Sometimes this can be avoided if you protect the top dog instead of the underdog.

Now, methods to break up fighting dogs such as to squirt them with water, toss a blanket over them so that they can’t see and are disoriented; or try noise aversion, which is making a lot of noise, may sound good; however, they’re easier said than done. These techniques are used to break up the aggression circle.

What if you already have two siblings adopted?

So, all this information is interesting, but what if you have already adopted two siblings? The most practical thing to do would be to re-home one of them. But this is hard and the most challenging situation for a dog owner to face. But if you do re-home one of them, say with a trusted friend or family member if it makes you feel better, the difference in the puppy remaining will be amazing. It’s in your puppies’ best interest in the long run, and the longer you delay, the more difficult it will be for them.

However, if you do decide to keep both puppies, there are some things that you can do to help in raising littermates, but it’s not going to be easy. You will need to create two different dogs with two distinct personalities and identities. You will have to do everything apart that you were doing all together. This would include:

• Walking them separately at different times

• Feeding them in separate rooms

• Training them to go outside and giving voice commands independently

• Crating them individually and moving the cages further and further apart each night

• Playing with them separately

• Letting them play together for only fifteen minutes for each playtime

• If they are taking puppy training classes, then you would take them individually if possible

Now, this is a strict regime to follow, but after twelve to fourteen months, they could become the dogs that they are supposed to be. They’ll may have their own personalities. They’ll be confident of their individual abilities. This may produce two dogs which are individuals instead of two halves trying to make one dog.

Littermate Syndrome and Breeders

A reputable breeder should tell the person who is buying puppies from them about this syndrome. You should also know that it can happen between puppies of different litters adopted together as well. The puppies can form this kind of bond upon adoption in the home. Still, some unethical breeders will try to sell two puppies together. If the breeder knows their business, then they are also aware of what happens with littermate syndrome and will discourage you from doing this.

If you want to end up with two dogs and raise them from puppies, then waiting until your first puppy is fourteen months old is the best way to go before you get another puppy. That way you can give all your attention to the one puppy, and it will be an experienced dog when you get your other puppy. It will be the best of both worlds.

Question: Have you ever experienced littermate syndrome with your puppies?

  • Sandra Dominguez

    Yes. I have two girls 4onths old. One girl is 4 pounds nd the other is 3 1/2 pounds. I have mom and dad in our home as well. The puppies have shown littermate syndrom . I am devastated. I dont want to give one up. What can i possibly do to keep both. Can i seperate temporarily fo another home so they don’t see each other?

    • dogtraining

      Hi Sandra,

      Thanks for the question. Yes, littermate syndrome can be quite devastating. We are sorry to hear of your challenges, but you’re not alone; many pet owners endure the same consequences of littermate syndrome. Yes, you could keep both; however, more than likely, it will require a certain living arrangement. In our opinion, you would have to be willing to keep them separated when unsupervised. It will require much consistency on your household as well as leave little room for error with respect to the safety of everyone concerned.

      Due to the dynamics of households this cab be a challenge in itself. Not every household can supply this level of consistency. Household with children, high traffic inside and out, pet owners that have long work hours should all be considered. As a matter of fact this is why some pet owners choose to rehome one of the dogs.

      At the end of the of the day, as you know, the choice is ultimately what is BEST for the dogs.

      Thanks again for connecting with us!

      Should you have any further questions, please feel free to contact us.

  • Sandra

    Thank you for reply. I am a stay home mom. Still undecided on re home. I have them separated in different rooms and rotating them throughout the day. Only one pup has syndrom. I am going to find training for syndrome pup and see if we can work this out. 😣

    • dogtraining

      Hi Sandra, Sounds good. Please feel free to contact us should you need detailed guidance/help. Thanks again!

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