I'm sure it's just a sign of dominance, but making sure. Boris is always grabbing Tips by the neck (shoulders I guess), usually strong enough to make Tips yelp a bit. Is it common between dogs to show their dominance? Usually afterwards Tips start nipping at him etc.. Does it mean he's not accepting it? This morning Boris kept Tips on his back and started sniffing his belly, and Boris didn't move, but after that he was on Boris' head chewing his ear. Should I be worried of fights because Tips won't accept Boris' dominance?