My son (6) and daughter (4) are chalk and cheese. He's sensitive and inward-looking and although he has friends he's happier on a 1 to 1 than in a group. My daughter is sociable and gregarious and infinitely annoying, but charming with it. And they seem to hate each other. Actually I think she would adore him given a chance but he's so mean to her. I give him lots of positive attention but he he thinks the world's against him and takes it out on his family, especially his sister. He says he hates her and wishes she wasn't around. Although I know siblings often fight, underlying it is a protectiveness of each other which he doesn't seem to have. I'm really worried about them and their future relationship and don't know how to turn it around and make them realise they are lucky to have each other and can be friends. Help?!