That’s the shocking charge from a longtime family friend, who kept a private record of the secret Kennedy family feud – and is now going public for the first time exclusively in The ENQUIRER.

Caroline Kennedy desperately campaigned for weeks to be the next New York senator – but she refused to support and bitterly attacked her late brother John when he wanted to run for the same seat.

Ironically, Caroline – who was pounded by political pundits for her lack of qualifications to replace Hillary Clinton – ridiculed her late brother’s ambitions and even taunted him that he would be shot like their father John Kennedy.

 "John was broken-hearted when Caroline coldly told him he didn’t have the political experience to run – something she became accused of," the Kennedy pal divulged.

"John felt as though she was jealous, that she did not want him to succeed."

The longtime family friend looked back over journals chronicling his friendship with John and decided to disclose the behind-the-scenes conflict because of Caroline’s surprise decision to urge New York’s governor to appoint her to the Senate seat being vacated by the former first lady.

And giving new ammo to Caroline’s critics, the family friend charges that the would-be senator had shown "zero interest" in politics until she stiffed longtime political friend Hillary last year by stumping for President-elect Obama.

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