Presidential candidate Robert F. Kennedy Jr. stands accused of sexually assaulting a babysitter over two decades ago, according to an exclusive report from Vanity Fair.

In 1998, Mr. Kennedy and his then-wife Mary Richardson employed the babysitter, 23-year-old Eliza Cooney, who moved into their home to care for their four children. One night that year, Kennedy, who was 45, allegedly rubbed Ms. Cooney’s thigh under the kitchen table, the report says.

Ms. Cooney documented the incident in her diary, expressing uncertainty about Mr. Kennedy’s state of mind, writing, “I wasn’t sure whether he was on something or really tired or was missing Mary or was testing me.”

The situation escalated when Mr. Kennedy reportedly entered Ms. Cooney’s bedroom, read her personal diary and requested that she rub lotion on his back — a request that she described to Vanity Fair as “totally inappropriate.”

Another incident occurred in the family pantry, where Ms. Cooney claims Mr. Kennedy groped her hips, rib cage and chest. This episode ended only when another staff member entered the room. Recalling the encounter, Ms. Cooney said, “My back was to the door of the pantry, and he came up behind me. I was frozen. Shocked.”

Ms. Cooney left the Kennedy household a few months later, documenting in her diary her desire to leave “bad men” behind.

The Kennedy campaign didn’t respond to Vanity Fair’s requests for comment.

Adding to the allegations, the magazine reports that Mr. Kennedy sent nude photos of women to friends while still married to Ms. Richardson. Friends believe he took the photographs himself, though it remains uncertain whether the women consented to being photographed or having the images shared.

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