My DS (10) has a friend sleeping over. He's a very sweet and gentle little boy. We were all chatting about which other school friends lived nearby and the little friend pipes up that X (who lives near us) bullies him. I didn't want to make a major issue out of it there and then but told him you must try and avoid X and if it continues tell your teacher. Should I mention it to his DM or to the school. I don't want to cause problems by sticking my nose in but equally don't want to ignore anything.