Since he was 2 yrs old my SIL's oldest ds has exhibited several disturbing behaviors that dr's have not been able to correctly diagnose or control with meds. His moods switch erreatically & frequently, from happy to uncontrollable anger in seconds. He has no empathy or compassion for anyone & often causes physical pain in his family members just bc he wants to. Physical discipline or threats do not phase him or change his behavior, this causes him to react more violently. He understands right from wrong & negative vs. positive consequences but does not care & will still do bad things or hurt people. His parents have taken him to therapists to try & figure out his problems but so far no meds have worked. He's been diagnosed as ADD/ADHD for the erratic behavior but he can sit & concentrate for long periods of time & it does nothing to help his attitude & lack of caring. He's extremely bright & creative as well, which often leads him to doing things that are very dangerous, he's grabbed kitchen knives & threatened to kill his parents or siblings. My SIL is at her wit's end & has no idea what other avenues to explore to help her ds. Has anyone experienced anything like this or have anything I can suggest to her?