A common mistake we make as pet owners is to add human emotions and concepts to our K9s. As trainers, one of the most common and problematic ways we see this is when owners keep siblings from the same litter. Individuals keep littermates with the genuinely lovely idea that they are keeping siblings together. Unfortunately, this misguided idea can lead to serious behavioral issues for one or both of your K9s, leading to something trainers have classified as Littermate Syndrome. 

Littermate syndrome happens when the two puppies have formed a powerful bond, learning and feeding off of each other’s emotions. While it is most commonly seen in dogs from the same litter, it can also happen if you simultaneously get two puppies very close in age. Littermate syndrome causes dogs to not go through their normal developmental process and takes a tremendous amount of work to overcome once it is present.

This can lead to behavioral issues in one or both of the dogs as they develop; these behaviors often include:

•Fear of people and other dogs

•Extreme separation anxiety

•Crate Issues

•Fear or aggression when encountering new situations when alone

•Leash Reactivity

•Higher incidence of aggression within the pack

•Aggression, even in breeds that are not prone to aggressive behaviors.

These issues often don’t present immediately and worsen as the dogs mature. So while our first recommendation is not to get littermates or dogs close in age, there are things you can do to prevent littermate syndrome if you have already found yourself in this position. 

Training Tips 

•Train each dog individually and then together. (The goal is to ensure that each dog forms a solid individual bond with the owner)

•Utilize an individual crate for each dog and never crate them together. You can start with the crates next to each other to ease the separation anxiety. Then, if the dogs do well, you should slowly move the crates to opposite sides of the room and then to different areas of the house. This will help the dogs start to feel independent.

•Plan outings with each dog individually. 

•Socialize your dog separately.

•Take a walk where each dog has a different handler. After walking together for a few moments, walk the dogs off in opposite directions and see how they react.  

•Make sure the dogs can adequately meet new dogs and people when they are together. Littermates tend to feed off of each other’s energy. So when meeting a new person or dog, excitement or fear will be amplified by having the other littermate present.

•It is essential to continue individual training/socialization trips and plan joint outings.

You should always contact a local trainer to help navigate this unique situation. Understand that the best step is to get ahead of Littermate Syndrome before behaviors and aggression become present. 

Author - Dina Lamberty/Larinda Watts