Jim @Chumley, I think that is play. Brutus and Frankie play like that as well. When Brutus is no longer playing he will show teeth and give a kind of screaming bark/growl where he has never bite Frankie but he backs him up very aggressively. The problem that I had with the last fight that led to meds is Frankie who is normally very submissive had enough and went back at brutus. No good at all. Scariest moment ever. dining room chairs where flying to try to break them up. you will definitely know the difference between play and real.