If you decide to bring a second (or third) dog into your home, you should always give consideration to training older dog to accept the new family members. Whether the dogs concerned are neutered or not, your best bet in bringing a second dog into your family is to choose one of the opposite sex. Although most sexually altered males get along with each other just fine, there are always exceptions, and with some dogs, this could lead to a very testy situation.
Bringing a second adult male dog into your home can be tricky, especially in some of the more aggressive breeds. Two entire male dogs (i.e., dogs that have not been neutered) in the same household will always bear watching. Problems between two females are usually less likely, but not entirely unheard of. Introductions should always be handled with care and consideration, with benefit of the doubt given to the resident. An adult dog with seniority may mistake a new puppy’s exuberance for aggression and react accordingly.
