MacKenzie Phillips

Mackenzie Phillips, the eldest daughter of the late John Phillips, frontman of the Mamas and the Papas, says her father raped her and that they later carried on a consensual incestuous relationship, People.com reported.

Phillips will appear on The Oprah Winfrey Show on Wednesday to discuss her new memoir, High on Arrival, and discuss her relationship with her father.

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The former One Day at a Time star says the first time she remembers her father having sex with her was when she was 19, the night before her wedding to Jeff Sessler, a member of the Rolling Stones' entourage. "On the eve of my wedding, my father showed up, determined to stop it," writes Phillips in her memoir, according to People. She says she passed out from drugs and woke up to find her father having sex with her.

Watch full episodes of One Day at a Time

She said after she was fired from One Day at a Time because of her struggle with drugs, she went on tour with the Mamas and the Papas and her sexual relationship with her father became consensual. He wanted them to run away to a country where their sexual activities would be acceptable, she said.

"He was completely delusional," she wrote. "No, I thought, we're going to hell for this."

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Mackenzie Phillips, 49, was born to John Phillips and his first wife, Susan Adams, in 1959. John Phillips fathered two other daughters, Bijou and Chynna Phillips, half-sisters to Mackenzie, who have different mothers. He also has two sons, Jeffrey and Tamerlane.