Mackenzie Phillips Says She Had Sexual Relationship with Father

Former "One Day at a Time" child star Mackenzie Phillips opened up to Oprah Winfrey about her alleged incestuous relationship with her father, The Mamas and the Papas lead singer John Phillips.

Phillips said her father started a sexual relationship with her when she was about 18 years old and claims the relationship continued for 10 years.

"It didn't happen every day, didn't happen every week, but it did happen many times," the actress told Oprah on Wednesday's "Oprah Winfrey Show" of the incest. "It became a consensual relationship over time."