I'm not a parent, but still... It seems to me that the system lacks a very special one-way channel of communication from a child to the parents, a channel that parents receive messages from, the kid knows it, but the kid thinks that parents don't know that the kid knows. If such a channel existed, then kid would sort of accidentally inform his parents about his thoughts. He would do it intentionally, but he would believe his parents would think it was an accident.