If you have more than one dog in your household, then you may be familiar with the term “littermate syndrome.” Littermate Syndrome, also sometimes called Sibling Aggression or Littermate Aggression, can cause behavioural problems in dogs of a similar age who are raised together.

In this podcast, LWDG Founder Jo Perrott discusses with LWDG Experts Emma Stevens and Abbie Reid what littermate syndrome is and how to deal with it if it arises.

What is Littermate Syndrome?

Littermate Syndrome is a set of behavioural problems that can occur when two puppies from the same litter , or pups of a similar age, are raised together.

The most common symptoms of littermate syndrome include resource guarding, separation anxiety, and difficulty with socialisation. While these problems can be frustrating for owners, they can be prevented through planning, and they are often easily resolved with the help of a qualified trainer or behaviourist.

Littermate syndrome is not a cause for concern and should not make you avoid getting a second puppy. With proper management and training, most dogs develop and mature to lead happy healthy lives.

‘Training littermates is a lot of work but if you put the hours in the rewards are certainly worth it! Abbie Reid

Littermate syndrome can affect unrelated dogs of a similar age

How to spot symptoms of littermate syndrome

The symptoms can vary from mild to severe, but usually include separation anxiety, aggression, and a strong bond with one another that can make it difficult for them to socialise with other dogs.

If you suspect your dog may be suffering from littermate syndrome, there are a few things you can look for.

First, pay attention to how they act when they’re apart from each other. If they become agitated or anxious, it’s a possible sign that they’ve become too dependent on each other.

Second, watch for signs of aggression, such as growling or snapping, when they’re around other dogs.

Finally, take note of how they socialise with other dogs. If they seem withdrawn or shy, it’s possible that they’re not getting enough exposure to other animals.

Pups with littermates syndrome may not eat or drink if apart

Tips for preventing and dealing with littermate syndrome

There are several things you can do to prevent littermate syndrome from developing in your puppies.

First, make sure to spend equal amounts of time socialising with each puppy individually. This will help them learn to bond with you and trust you as their primary source of comfort and security.

Secondly, provide plenty of opportunities for your puppies to play with each other so that they can learn how to interact appropriately.

Finally, be patient and consistent with your training, and make sure to plan to work with each dog in the way they need you to. Remember to work with the dog in front of you at all times.

“Be prepared for two puppies to be twice the work of one,”                       Dr. Heather Graddy

We hope this podcast and article have helped you learn more about littermate syndrome and how to prevent it. If you have any questions or concerns, please do not hesitate to reach out to us for support.


Littermates can be a joy to raise together if done correctly.

Our team is here to help you with every step of your dog training journey. That’s why we offer our Society Squad live coaching calls  so that pet owners like you can ask our group of experts any questions they may have about this condition or any other behaviour problem their pet is experiencing. Thanks for reading!

Link to Dual Handling Masterclass

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