I have a 5 year old son who is a wonderful, respectful and caring boy, 80% of the time. During the remaining 20% of the time, he is disrespectful, angry, moody, and yelling at my 13 year daughter and myself as much as possible. He turns red in the face. He punches. He puts his face right in mine and tries to bully me around. I remain as calm as possible. His behaviour starts whenever he doesn't get his way. My daughter never behaved this way, so it's very difficult for me to understand how to handle him, or how to react to his behaviour. I have no experience. Every day we run into problems. I would appreciate help and advice because this situation has drained me emotionally and made me quite sad.