D..
Ask your ped for an evaluation with a play therapist. Let her see what triggers his stressors. Write down everything you see that is a problem and give it to her in an easy-to-read format. Go about your day with your children in front of her as you normally would.
She will give your ped and you some good advice on how to proceed with him. I believe she will recommend an OT to work on sensory integration issues at the beginning.
Please try this - I really think this is a more helpful thing than reading books at this point.
Good luck, M..
Dawn