9. They are cruel to others.
This is the end of the anger road. The behavior has become an end in itself. Hurting someone because he was angry with them was a serious problem. Hurting them just to see them suffer is very sick behavior. Here is the problem. Although a little teasing and tormenting usually is only good fun, too much is a serious problem.
It works like this. When children are about four or five, they begin to see things as others see them. It is sort of like they can go into the other person and feel what they feel. This is called empathy. By grade school, they do this fairly automatically most of the time. One value of empathy is knowing when other people are hurting physically or emotionally. If they are, the child feels badly and wants to help. This is how she tells when enough teasing and tormenting are enough. When it stops being fun and starts hurting, enough is enough. Knowing just when to stop is a problem. But most children know about where the line is and respect it.
Children who are cruel on purpose and get pleasure from it are across the line. They want to see the other person suffer. Empathy or the pain of the other person does not stop the behavior. Usually, children showing this sign have themselves been victims of the behavior. Children learn what they are taught.
Here is an important point. Be sure no one in your home torments your foster child physically. Keep teasing to a minimum. Also be sure no one tries to get back at him. Do not try to teach him a lessen by hurting him. For example, biting him to teach him not to bite is a very bad idea. He needs gentleness, firm guidance, and a predictable family. Also, talk with him about his behavior, the feelings and pain of others, and about his angry feelings.