Soap opera actress Mackenzie Phillips claims she had a 10 year consensual incestuous affair with her own dad, Mamas and the Papas singer John Phillips. 

Sick!

Mackenzie, 49, tells her tale of woe in her new autobiography, High on Arrival.

She claims her dad turned up at her house the night before her wedding and the pair took loads of drugs and passed out in bed together. She continues:

"My father was not a man with boundaries. 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 father."

She joined the revamped version of the Mamas and Papas with her dad when she says their relationship became consensual. Spew.

"We're touring and I begin waking up after drug-fuelled events with my pants around my ankles and my father sleeping beside me. It didn't happen every day. It didn't happen every week, but it certainly happened."

However, her ex step-mother, actress Michelle Phillips isn't convinced.

"John was a bad parent and a drug addict but fucking his daughter? If she thinks it's true why isn't she with a very good psychiatrist on a couch? I have every reason to believe it's untrue. Mackenzie has a lot of mental illness. She's had a needle stuck up her arm for 35 years. She did 'Celebrity Rehab' and now she writes a book. The whole thing is timed."

This whole thing is seriously effed up whatever the truth is...