It depends on the individual case. Thank goodness my little ones are not dealing with this situation but I am 29 and was diagnosed just a little bit older than your son due to a traumatic experience. It is very difficult for anyone to cope with these issues but, in my experience, so much harder as a child that has not fully learned their own coping mechanisms. I hope you can find help for your son and I am here to talk anytime you need. :-)
try NAMI I'm a member too