Former child star Mackenzie Phillips has publicly dealt with drug addiction, arrests and divorce, but the actress’ memoir “High On Arrival” reveals she engaged in an incestuous relationship with her father, John Phillips of the Mamas and the Papas.

People reports in the book Phillips recalls the time she had sex with her father on the eve of her wedding to Jeff Sessler. She was 19 and already abusing drugs.

“My father showed up, determined to stop [the wedding,]” Phillips writes. “I had tons of pills, and Dad had tons of everything too. Eventually I passed out on Dad’s bed.”

“He was full of love, and he was sick with drugs. I woke up that night from a blackout to find myself having sex with my own father,” she explains.

“Had this happened before? I didn’t know. All I can say is it was the first time I was aware of it. For a moment I was in my body, in that horrible truth, and then I slid back into a blackout,” Phillips adds.