Littermate Syndrome in Dogs: What it is and How to Fix it

We’ve all been there to some extent. We show up to adopt one puppy and are very tempted to adopt another. Most of us don’t (or can’t) give into this temptation. However, for those that do, you have to watch for littermate syndrome. 

The “condition” is more of a behavioral problem than a health problem. It occurs when puppies become too engraved with each other, causing behavioral challenges. For instance, they may suddenly become extremely confrontational around puberty, or they may develop isolation anxiety towards each other. 

Luckily, there are ways to treat and prevent this condition. However, it is important to be informed before your puppies get too old. Preventing is far easier than curing. 

Identifying Littermate Syndrome 

Littermate syndrome does not always occur when two puppies from the same litter are kept together. It is not an eventuality or a healthy mode of existence. 

There are two different types of littermate syndrome. The first type occurs when the dogs form too strong bonds with each other. They become overly dependent, which can cause separation anxiety and similar issues.

Dogs may also become more aggressive towards other dogs, especially when not properly socialized. They may dislike any dog that isn’t their sibling. Sometimes, these differences are not even. Only one dog may be dependent on the other. In these cases, the dependent dog may just follow the lead of the other.  

The second type involves increased aggression towards each other. This occurs mostly when your dogs are the same gender and hit puberty. 

Littermate syndrome occurs most often between 8 to 16 weeks. During this time, puppies will begin socializing with the outside world. If this isn’t done, they may become extra attached to each other. 

Behavioral issues may get worse as your dogs reach sexual maturity. 

Some breeds may be more prone to this issue than others. Those that are more pack-oriented may be particularly prone to this issue. Those that are more people-oriented tend to be less prone to littermate syndrome.

Littermate syndrome may be more common in dogs of the same gender, too. Males may get particularly territorial towards each other, too. 

Impact of Littermate Syndrome 

While it isn’t commonly talked about, littermate syndrome is a big deal. It can impact a puppy in several ways, directly impacting their ability to function in our world.

Dogs with littermate syndrome have issues socializing with other dogs. They may be particularly difficult to socialize. Many may become aggressive towards other dogs after they reach puberty. They may become fearful and aggressive whenever they meet a new social situation, which can potentially make them aggressive towards other people, too.

Littermates often develop separation anxiety towards each other if they are not separated for considerable periods. Their very strong bond can also make training challenging. The dogs may not pay enough attention to their owners for training purposes. Often, you must separate dogs for training, but if they aren’t used to being separated, this may only cause separation anxiety. 

Often, littermate syndrome causes a lot of unnecessary stress on both dogs. Long-term stress can cause health issues and impact the quality of life of both dogs. 

Therefore, diagnosing and treating littermate syndrome as early as possible is important. The earlier you treat it, the easier it is to fix. 

Prevention 

The easiest way to prevent littermate syndrome is to not adopt littermates. If you want two puppies, waiting to adopt another puppy from a different litter is helpful. Even if there is only a small age gap, it’s often enough to prevent littermate syndrome from occurring. Plus, this also helps you start training and socializing the first puppy before getting the next one. If at all possible, this is the best route. 

If you do adopt two dogs from the same litter, we recommend allocating dedicated time to each puppy. It will take twice as much time to train and socialize two puppies as one. You cannot just have one dog “tag along” with the other. When training and socializing, always separate the puppies whenever possible. If you enroll them in group puppy classes, enroll in classes at two different times. 

At home, cultivate time for one-on-one bonding, as well. You should not only interact with the puppies as a unit. Crate training the puppies can be exceptionally useful, as this will help them learn to be alone in a positive way. 

Tailor your training sessions to each puppy and seek help from a professional as needed. Your puppies probably won’t progress in training in exactly the same way or exactly the same rate. It’s important not to compare puppies to each other and allow them to progress on their own timeline. 

Training 

If your puppies already have littermate syndrome, there is a lot you can do to help reduce the effects of this syndrome or even eliminate it completely. 

In most cases, though, you’ll need the help of a professional trainer. This process can be challenging for both you and your puppies. You may have to make significant changes to your lifestyle to accommodate the changes your dogs’ needs. 

Because littermate syndrome can appear in several different types, you’ll probably need a specific training plan to resolve the particular problems exhibited by both of your dogs. 

Generally, fixing littermate syndrome includes gradually separating the puppies. Doing this too fast can cause distress, though. Therefore, you’ll need to start small and slowly increase the amount of time dogs spend apart. Slowly increasing the time they spend apart can help eliminate littermate syndrome. When separated, you should train and socialize them separately. This helps ensure that your canines learn to be apart and increases their independence. Even playing a very basic game like fetch can help each dog build confidence in being separated from the other dog. 

Socialization is vital while you’re trying to make each dog more independent. Your dog will need to learn how to interact with the world when alone. It’s important that they learn how to do this properly. Gradually expose your dog to new experiences. Group training sessions can be very useful at this point. Use positive reinforcement techniques to encourage proper behavior while out socializing. Keep these experiences as positive as possible. 

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