she’s sort of a special-needs child

Haha. Good one. That’s exactly it. Ruminator Ron is an attention seeking child. I think your stance is make peace with all your selves especially the troublemakers. Have some patience with them. Try different strategies so they can get along.
My approach is actually to ask him to leave. Send him to a special needs school. I can’t control him when he gets in that mood. He’s potentially dangerous to self and others. If he has to stay, better to just sit quietly and watch the others.
Or one option is for him to ask to change his name? No that is desperate… 🙂