This might be a strange question but I am going to go ahead and ask it! My 5 (nearly 6) month old puppy won't stop mounting dogs, both my other dogs and dogs in the park. It's usually the male dogs and there are certain dogs in the park that he will mount all the time. Is this normal? He has been doing it since he was 3 months old but has only recently started with two of my German Shepherds (1 dog, 1 bitch). My female isn't neutered. At the moment she isn't having any of it and tells him off, but I'm afraid in a few months time she will change her mind. Should I get him neutered asap?