I have an almost 3 year old red. She is a big baby, but play sometimes leads to biting. It’s not really biting, though. She nips and releases. I feel that it’s hjow dogs play. That’s how they play with each other. They nip each other’s ears and jump on each other. I don’t think it is in aggression, so I don’t worry about her. I DO, however, worry about mine’s jumping, but I will look at another post for that. I have heard that using a spray bottle with some water in it is supposed to work, but I have a water dog. She loves water. She tries to bite the water as it comes out of the hose in the summer and as it comes from the faucet in the winter when we give her baths. I try to ignore her when she nips, but she jumps on me when I ignore her. It’s pretty difficult to ignore a 65-70 lb pit bull jumping on you… lol The jumping is a work-in-progress situation, though.