Do you think that he reacts to your behaviour? If you're strong and in control, he doesn't feel a need to act up. It's just a suggestion. I don't mean to press all your mom-guilt buttons.
Like you say, feeling strong and in control is helped by reaching out to others, and such is the human condition. I love the lines from Younger than Springtime (South Pacific): "I touch your hands And my heart grows strong, Like a pair of birds That burst with song."
CAP is also a great program. Good people, and a marvelous introduction to the world of aviation and aero-engineering and science. Thanks for volunteering, @Melvinotis.
When I was a kid, I used to hit my sister. My dad had a serious talk to me about controlling my anger. That helped my development.
I forgot how young he is, and I would worry more later if he doesn't get better. I can't remember if/when you've moved household, but that could be a short term stress on both of you.