We will be getting a second dog so Benji will have a playmate. My question is; If we get another male dog, will there be problems like fighting even though Benji is almost 2 years old and the dog will be getting is a puppy? Or should we get a female dog? Benji is neutered and if we get a female she will be spayed. Can 2 neutered male dogs be kept together in the same house?