CHICAGO — Actress Bijou Phillips says she knew her half-sister Mackenzie Phillips had consensual sex with their father, Mamas and the Papas leader John Phillips.

In a statement read by Oprah Winfrey on her talk show Friday, Bijou Phillips says she was 13 years old when Mackenzie Phillips told her about the sexual relationship.

Bijou Phillips is now 29 and says the news was confusing and scary. She says it was “heartbreaking” to think her family would leave her alone with her father.

Appearing as a guest on “The Oprah Winfrey Show” Friday, Mackenzie Phillips said their father “had changed his ways as much as he was able to” and she felt Bijou Phillips was safe.

Mackenzie Phillips says she did go get her sister when she “felt like she wasn’t being watched properly.”