Actress Mackenzie Phillips said in a memoir published on Wednesday that she had an incestuous affair for years with her father John Phillips, the late singer with 1960s band The Mamas & the Papas.

In the memoir High Arrival, which was published a year after she was arrested for cocaine possession, Phillips writes that she had sex with her father at age 19, the night before her 1979 marriage to Jeff Sessler, a member of the Rolling Stones' entourage.

The former star of TV sitcom One Day at a Time said she and her father used drugs that night. John Phillips died in 2001.

My father was not a man with boundaries, Phillips writes. He was full of love, and he was sick with drugs. I woke up that night to find myself having sex with my own father.

Phillips' half-sister, Chynna Phillips, told US Weekly magazine she believed Mackenzie's story. Chynna said Mackenzie told her in a 1997 phone call about the incest and that it lasted for 10 years.

Somebody could have dropped a piano on my head and I probably wouldn't have felt it, Chynna Phillips told US Weekly. But I knew it was true. I mean, who in their right mind would make such a claim if it wasn't true.

Mackenzie Phillips, 49, starred in One Day at a Time from 1975 to 1983 and has a long history of drug abuse. She was fired from the show at one point after undergoing drug rehabilitation but then relapsing.

In August 2008 she was arrested at Los Angeles International Airport with drugs hidden in balloons and plastic bags. She pleaded guilty to cocaine possession and was sent back to drug rehabilitation.

Mackenzie Phillips' marriage to Jeff Sessler ended in 1981. She has married twice since then, and has appeared sparingly in TV dramas in recent years.