Carly Simon Said JFK Was with His Mistress When Jackie Kennedy Gave Birth

Carly Simon is opening up about her friendship with Jacqueline Kennedy Onassis, and shedding some light on the late former first lady's feelings about her husband's affairs.

In an interview with NBC News about her memoir, Simon said that JFK wasn't present for the birth of one of his children because he was with a mistress. She told the outlet that Jackie was sometimes hurt by his behavior — "For instance, his not being there for the birth of a child, his being off with a mistress while she was in the hospital," Simon said. "There are various things that he did that by comparison to having a mistress must have hurt more."

In her book, Touched By the Sun, Simon wrote that "in a cheerful but resigned way," Onassis told her "of course she knew about" his affairs, but “she just didn't mind their presence as much as she might have. Because she knew he loved her much, much more than any of his dalliances.”

JFK and Jackie had three children together; Simon doesn't specify which birth she said JFK wasn't present for.

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In the interview, Simon also opened up about her unlikely friendship with Onassis, telling NBC, "I think she saw in me something that she wanted to have a little bit of herself. I think she saw a free spirit who had the license to be, in a rock and roll kind of way, loose as a goose. And I could smoke a joint if I wanted to."