Can't stay now ... but just wanted to mention that you might want to think twice about telling your S6 not to talk to anyone outside the family about this, that puts pressure on him as if this is his secret and that's a lot of weight for a 6 year old to carry. He needs to be able to talk too, and right now he's confused and angry and neither you or your H are his first choice for confidants .... have you talked to his school guidance counsellor or his teacher to tell them what's going on?
Just my two cents ...
Holding onto anger to punish someone else, is like lighting yourself on fire to get smoke in their eyes ~ 25yearsmlc