Anonymous wrote:OP here, any other insight?
It isn't acting up. It isn't mental health or a disability. It's a jerk doing lowkey bullying. It happened when we went to school and it happened when our parents went to school.
School can't do anything about a single incident because they can't prove that it was intentional.
The only things you can do is work with them on their dodgeball skills, teach them a means of proportionately retaliating, and helping them figure out a way to not publicly react to it.