Sorry for long comment... I stutter also, I am 28 years old, I stuttered a lot when I was a child, then in my teen years I almost didn't stutter at all, and even those few blocks I had were fastly overcomed and didn't even give af, now I stutter more.... Why am I saying this? When I was a kid I stuttered a lot, in my teen years I had rich social life and lot of fun and laugh in usual day of life, so with time I almost completely stopped stuttering... When I moved in new country seven years ago I fell into depression and all that "sad crap", so I started stutter more, I could barely speak, and last 2 years I speak more and I stutter much less...but still stutter quite a bit... Now, my point/advice is push your child to be more social, teach him to be more social, you are grown man you gotta have something in your head you can teach him, having rich social life and general confidence with time is basically the key of getting rid of stutter. Make him do sports, martial arts, generally speaking art and shit, don't make him confident by making a piece of shit human out of him, make him a complete human instead, smart confident feeling good about himself and being true to yourself should give you nice life and make stutter side thing that will dissapear at some point.