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Dear Crystal,

I just adopted a 2-month old puppy that is so energetic and playful. She loves to play with other dogs and seems to prefer puppies to older dogs from what we can tell. We want to adopt another puppy to give her a playmate. We are hoping this will help her behave better if she has someone to play with. She is a great puppy when she is tired and we just love her so much. What are your suggestions for picking a good playmate for her?


Exhausted Puppy Mom

Dear Exhausted,

It sure is an exhausting business raising a puppy! There are so many things that we need to be doing for our puppies to make sure that they become friendly, happy adult dogs. The window for socializing puppies ends around 16 weeks. This is the period of time where we must be exposing them in a positive way to the things in the world that we need them to be comfortable with. This is job number one with a puppy. Secondly, you need to be starting training now with your puppy at home to create rules and boundaries so that when she is an unruly adolescent we will have a good foundation in place and she will be more likely to listen. Think about your 13-year-old throwing a temper tantrum but she doesn’t understand English and has a mouth full of very sharp teeth! We need to have that training in place to help our rebelling adolescents. That is a lot to do in my opinion. When you add another puppy you have to do all of that twice and separately. You thought you could just do both at once, didn’t you? Let’s talk about the risks of adopting two puppies and what you need to do to raise both puppies to be friendly and happy dogs.

The biggest concern that most professional dog trainers and behaviorists have with adopting two puppies is the fact that they almost always tend to bond very closely to each other to the exclusion of a meaningful relationship with the humans in the home. This phenomenon is known as Littermate Syndrome. It should be stated that there have not been studies on this syndrome, it is all anecdotal evidence. Even though the puppies would not be actual littermates, the risks are still the same.  They are going to spend a lot more time with each other than you and they speak each other’s language. They can become so hyper-bonded that when they are separated they can experience separation anxiety, anorexia or even aggression. This might be when you take one for a walk, training class or maybe one of them has a health problem and needs to be hospitalized or on crate rest. It can also be more difficult to train these puppies. According to applied animal behaviorist, Patricia McConnell, “It’s just hard to get their attention. They are so busy playing with each other…that you become the odd man out.”  Aggression or bullying can also be a risk for these same age pairs. If the two dogs are of similar size and personality, they may be more competitive for resources.

If you feel that you can meet the challenge of two puppies, I will outline some suggestions to try to prevent Littermate Syndrome.

  • The puppies should spend a lot of time separately. They should definitely be crated separately. One crate for two puppies is too small and definitely won’t help avoid them over bonding. I don’t even want to think about the mess that two puppies could make in a crate or even in an exercise pen.
  • You will need to walk each puppy separately as well. In addition to spending time with each puppy alone, it is pretty hard to leash train a dog in the presence of another dog.
  • You should definitely attend a puppy socializing class with any puppy under 16 weeks and that should be done separately. You should not assume that they will be fine with other dogs if you don’t take the time to socialize them with other dogs. I recommend a few different ways to make puppy dates. You can ask your vet if they have any other clients with puppies, you can ask your friends or you can find a socializing class that has an element of puppy play incorporated. Be sure that your class includes socialization exercises and is not just a puppy obedience class.
  • After 16 weeks, I will suggest that you take each puppy to a manners training class as well. When you are practicing your training at home you will likely need to crate one puppy while you train the other so that is another good to reason to get them used to being alone as well.

In the end, my recommendation would be for you to hold off on adopting another dog until you have had the time to socialize and train the puppy you have. Puppyhood is definitely rough but you can make it better by really investing time with your puppy. I suggest feeding from enrichment feeders, daily training sessions, several short play sessions throughout the day and also daily quiet time with your puppy. This is the time to form a lifelong bond with your new family member and be sure to start them off on the right paw. Another option is to consider adopting an adult dog that is out of its socialization period. They will be less likely to form an unhealthy relationship and it would be somewhat less work for you. There is still some work involved with an adult dog though so I still would suggest that you wait. I hope that now you can feel like you can make an informed decision whatever you decide to do.

Until next time,


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