What is Littermate Syndrome?

Angela Vuckovic
by Angela Vuckovic

If you think that raising a single puppy is hard, try rearing two (or a few) of them at the same time! And if they are born at the same time, whew – prepare to arm yourself with a lot of patience because of so-called littermate syndrome. 

Littermate syndrome is a term used to describe a set of behavioral issues that can arise when two puppies are raised together in the same household – while they can be from the same litter as the name suggests, they don’t have to be related, it’s enough they are the same age. While it's not guaranteed to occur in all cases, it is a common concern when simultaneously raising two puppies born at the same time.

Littermate syndrome typically manifests as a range of behavioral problems, so we’ll go over these together in order to better understand this common issue amongst canine siblings.

What are the Main Aspects of Littermate Syndrome?

Just like us humans, puppies too can develop many emotions and feelings for their siblings. However, in the canine world, this bond can manifest itself as a range of behavioral issues that owners can have a hard time rooting out. Here are the main ones:

  • Strong bonding:

Littermates may become overly dependent on each other, leading to anxiety when they are separated. This is especially common when you are raising just two puppies from a litter. As their bond grows, it will be hard to separate them – it can result in torn furniture, incessant barking, howling, or even depression. Here, redirection will be the key so find some  fun puzzle toys for puppies that will provide enrichment and pique their interest away from their partner in crime. 

  • Aggressive behavior:

In some cases, littermates may display aggressive behavior toward each other or other dogs in the household. This aggression can escalate as the puppies mature and vie for dominance within their relationship. At first, this aggression seems like some fun and energetic play, but as the dogs grow mature, it can escalate into actual violence.

  • Poor Socialization: 

At other times, littermates may fail to socialize adequately with other dogs and people because they spend most of their time interacting with each other. As they depend on their closeness, they will shun all others around them as a result. 

  • Difficulty with Training: 

If you raise littermates, remember that training two puppies at the same time can be challenging, as they may be more focused on each other than on their owner's commands. This can lead to disobedience and a lack of responsiveness to training. They would always look at their sibling’s reaction first, disregarding you. If you attempt to train them yourself, arm yourself with  tasty reward treats in order to make things easier for you.

To prevent or manage littermate syndrome, it's often recommended to raise the puppies separately for at least some period of their early development. This allows each puppy to establish its own identity, develop independence, and bond with their human family members. Proper socialization and training are crucial for each puppy to ensure they grow up to be well-adjusted and obedient dogs. 

If you are considering raising two puppies from the same litter, it's essential to consult with a professional dog trainer or behaviorist who can provide guidance and help you develop a plan to prevent or address littermate syndrome if it begins to manifest. Early intervention and proper management are key to minimizing the potential issues associated with raising littermates together.

Keep in mind that raising siblings from one litter can require more time and patience than raising a single dog. Still, with enough dedication, your pups can grow up into healthy and happy dogs!

Angela Vuckovic
Angela Vuckovic

A proud mama to seven dogs and ten cats, Angela spends her days writing for her fellow pet parents and pampering her furballs, all of whom are rescues. When she's not gushing over her adorable cats or playing with her dogs, she can be found curled up with a good fantasy book.

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