Hello, I'm 25 years old and I've stuttered since I was a kid, so I have a little bit of experience. Here's an interesting fact: I don't stutter when I'm alone. When I'm talking to myself alone, I'm more at peace than when I'm around people. So I'm assuming that your son feels fear, to some degree, when he's around others. Ask him if he stutters when he talks out loud to himself, that would be an interesting conversation. If you want to truly help him stutter less, find out what makes him nervous/afraid/anxious, and remove those things from his life. Truthfully, I wish that's what my parents would have done.