The screen goddess was embroiled in affairs with both married JFK and his brother Bobby during her troubled life that ended at age 36.
At one point, Jackie confronted the actress about her husband!
As GLOBE reported in 2012, author Darwin Porter's book, Marilyn at Rainbow's End revealed that Monroe was totally smitten with JFK and they first made love in 1946.
They reconnected at a Beverly Hills party in 1954, when JFK was married to Jackie, and Monroe was wed to baseball star Joe DiMaggio, according to the book.
JFK and Monroe resumed their affair and she had dreams of being First Lady one day, Porter wrote.
The playboy politician even invited Monroe to the home he shared with Jackie in Virginia, the book stated.
In These Few Precious Days: The Final Year of Jack with Jackie, author Christopher Andersen quoted the late actor Peter Lawford, who married JFK’s sister Patricia in 1954, as saying Monroe called Jackie to confess to the affair and to tell her that her husband had already agreed to leave his family and set up a home with the actress.
But Jackie became First Lady after JFK won the Presidency and in July 1962, about a month before Monroe's death, Porter wrote, JFK's wife requested a meeting with the star.
Monroe had been threatening to go public with her affairs with JFK and RFK—and Jackie wanted to put a stop to that during their meeting at New York's Carlyle Hotel.
"Jackie begged Marilyn not to publicly humiliate her children in front of the world," Porter wrote in his book. "She also pleaded with Marilyn not to make John Jr. and Caroline the victims of a divorce."
Monroe reportedly promised she'd never spill the beans—not knowing she only had days left to live.
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