The New York Post runs some tidbits today from the new book Bobby and Jackie: A Love Story, which purportedly reveals some steamy, sad secrets of a long-hidden affair between Jackie Kennedy and her brother-in-law, Robert Kennedy.

The pair supposedly came together after JFK's assassination, first as a means to express their grief, then as a means to express their passion. Camelot insiders, including Bobby's wife Ethel, knew the affair was going on, but everyone knew that it would never go anywhere—because it was the 1960s, because they were Catholic and divorce was what it was, because Bobby couldn't risk a marital scandal if he hoped to take office someday. So the pair continued in secrecy until Bobby's assassination in 1968.

Some factoids from the book, which includes witness accounts from Jack Newfield, Gore Vidal, and Truman Capote:

Six months after JFK's death, during a May 1964 dinner cruise on the presidential yacht the USS Sequoia, Bobby and Jackie "exchanged poignant glances" before disappearing below deck, leaving Ethel upstairs. "When they returned, they looked as chummy and relaxed as a pair of Cheshire cats,"

At the Kennedys' Palm Beach estate during Christmas 1964, socialite Mary Harrington saw Jackie sunbathing topless, with Bobby kneeling at her side. "As they began to kiss, he placed one hand on her breast and the other inside of her bikini bottom," Harrington recalled.

According to Gore Vidal, "The one person Jackie ever loved . . . was Robert Kennedy."

Shipping tycoon Aristotle Onassis — RFK's rival for Jackie's attention — once threatened to "bring down" Bobby by going public with details of the affair. "I could bury that sucker," Onassis said, "although I'd lose Jackie in the process."

On June 4, minutes after winning the California primary, Bobby was fatally shot by Sirhan Sirhan at the Ambassador Hotel in Los Angeles.

Jackie flew to his bedside — and Ethel allowed her time alone with the dying RFK, according to the book.

Bobby was brain-dead, but a distraught Ethel refused to pull the plug, and brother Ted Kennedy was in no shape to make the call, Heymann writes.

At 1:20 a.m. June 6, 1968, Jackie Kennedy ordered the respirator shut down and signed the consent form, the book reveals.

So, yeah, there you have it. The only sad, melancholy thing to ever happen to the moneyed, mossy Kennedy clan.

Image via Getty