He would lie to get sympathy. If you haven't noticed, its almost a fad now with the famous to claim bipolar.
I'm not trying to come off as defending this guy or his family. I can't stand the Kennedy's. I'm just a wit bit sensitive to these issues due to my own experience with my daughter. It is hell and for the family. One reason why I would believe he is bi-polar because of his family histroy and it would explain why his family are all narcissistics.