Is rejected or ignored by most people his age:
This is the same as the last sign, except it is actually true: most people dislike your child. It is even worse if he does not understand they do not like him.
Start by being honest with yourself and with your child. Your helping him starts with determining why he is so disliked. Since you are unlikely to have enough objectivity to see what others see, you might start by asking your child’s teachers, other parents who you think will be candid with you or other adults who interact with your child. Also, do not overlook the obvious. Other children have likely told your child why he is disliked. If you are patient, sensitive, and listen carefully, you will normally be able to learn the facts of it by asking him. With that information, you and he can work on changing or compensating for those characteristics others find objectionable.
