My puppy is 10 month old. He started to use his mouth about a month ago when playing with me. It really doesn’t bother me but, I have children and I don’t want him to think that he can do the same with them, plus I think that he just might be challenging my authority or leadership with that. I don’t want to make him shy but I want to watch over my kids. He is a strong puppy. What should I do?