On September 23, 2009, former One Day at a Time
star Mackenzie Phillips appeared on The Oprah Show
to reveal a shocking family secret she'd kept for years. She told Oprah that she'd carried on a sexual relationship with her father, John Phillips, the founder of the Mamas & the Papas, for approximately 10 years. See how her story has inpired other survivors of incest to speak their own truths.