No, sorry. there's no 'curse'. It's 'the family way' learned and passed down by 'grandpa' Joe Kennedy. Bootlegger, Mafia Associate Hoodlum, Hollywood big-shot womanizer, Nazi sympathizer, and all around creep who thought HE and all his male spawn were above The Law. And who, in his spare time had his own daughters Lobotomized because 'she embarrassed the family' (she was 'slow' or 'mildly retarded' as they said back then).
Then, on JFK's wedding day to Jackie old man Joe pulled Jack aside and said: "Just because you're married now doesn't mean you can't see other women." (Gee thanks dad). And as we know Jack sure took that advice to heart and followed it -- more than hound-dog Billy-Jeff.
Which brings us to Marlyn Monroe and her Murder. More than likely committed by that other POS, U.S. Attorney(ha!) Robert F Kennedy, who lied about his whereabouts that night -- and who was now getting sloppy 2nds from Marlyn after Jack -- Bobby's Brother-In-Law Peter Lawford, and some Kennedy goons. Carried off by using a Hypo full of a barbiturates (needle mark found on one of her buttocks) and staging a phony 'suicide scene' with an empty pill bottle (She had to be whacked as Jack talked too much).
This 'Kennedy's can get away with anything' attitude even carried over to first cousin Michael Skakel who Murdered teenage neighbor Martha Moxley in 1975 with a Golf Club. He admitted to a friend he met in drug habit (whatta shock!), "We're Kennedys. We can get away with murder."
So there is no 'Curse', it's a family of GD degenerates. Satan even has a special Kennedy Wing in HELL for them!
(sorry but I'm 1/2 Irish and these 'people' are an embarrassment to all Irish and just disgust me!)
I'm 1/3765 Cherokee and I'm going to Harvard.