Its important to understand the difference between play growling and real aggression, puppies often growl when they play and its just a way of saying that they are enjoying it. However when/if you really think he's being agressive just stop what you are doing, pick him up and remove him from the room, only for a minute or 2 but enough time so that he realises that when he behaves that way, he gets no attention.
__________________ Indy, Benjamin and Malachi   There is no psychiatrist in the world like a puppy licking your face- Ben Williams |