Sibling relationships can be complicated, both for humans and dogs. When adopting a new pet, people often think it’s better to get two from the same litter. With cats, that is a good strategy. Most veterinarians recommend adopting cats in pairs.

With dogs, it can be a problem. Littermate syndrome is a very real and serious issue.

Littermate syndrome occurs when two puppies from the same litter develop such a strong attachment to each other that it interferes with their ability to interact in a normal manner with other people, other dogs, or any situation where they are not together. Puppies with littermate syndrome become highly dependent on one another for a sense of safety and normalcy. Littermate syndrome can affect dogs of any breed, and it may also affect unrelated puppies who are adopted at the same time and raised together.

Signs of littermate syndrome can include excessive crying, whining, and destructive behavior when siblings are separated from one another, a lack of interest in playing or interacting with people or other pets, and fear of unfamiliar people, things, places, or noises. Dogs experiencing littermate syndrome may only want to eat if their sibling is present. Training two puppies from the same litter may take longer than expected because puppies are so distracted by one another.

Littermate syndrome is difficult and stressful for pet parents to deal with, due to the numerous behavioral issues that are involved. Because puppies with littermate syndrome dominate each other’s attention, they may fail to learn how to communicate, play, and socialize with other dogs, and may bond less with their family. Over time, it can result in fear and aggression. In the worst-case scenario, littermates may attack each other. If two sibling dogs play or fight too hard, it can lead to severe injury or death.

For these reasons, adopting two puppies at a time may mean more work, not less. Usually, formal training is required, and each dog will need to be trained separately. The goal is to get each dog comfortable with being alone, meaning separate walks, separate food bowls, separate training, and separate crates.

Rehoming one dog is the last resort. It comes down to safety and happiness. Aggression should never be taken lightly or overlooked. An aggressive dog is not a happy dog — and dogs deserve to be happy.

My name is Bonnie, and I’m a fun, sweet, loving boxer who is extremely well-behaved in the house. I like to go on car rides and adventures, love to hike, and enjoy running in the yard. I’m also a great cuddler and will be an instant friend to whomever I meet!

Second Chance Humane Society’s Animal Resource Center and Thrift Shops have served San Miguel, Ouray & Montrose Counties since 1994. Adoption hours are Tuesday through Saturday from 11 am to 5:30 pm. Our Community Veterinary Services are available by appointment. View our shelter pets and services online: