thank you for answering me. to answer your questions: yes, I have asked my 18 year old why he is mean to his younger brother and he just says he can't stand him. my 18 year old is an athlete and a musician. the younger brother is smarter in school and has a yappy mouth that does annoy his older brother but in all fairness his older brother has been mean to him since infancy. yes, my 17 year old son is the ONLY person my 18 year old is so mean to. my older son is a HERO at school, captain of the soccer team and all round great citizen. But at home, with his brother, he goes between verbally bullying him to totally ignoring his existance. the relationship between my older son and me is usually great but he doesn't like it when I ask him to be kinder to his younger brother. he sees him as "weak".