Stepsisters Mackenzie Phillips, Chynna Phillips to appear on Oprah together!

Mackenzie Phillips shocked everyone by confessing to a decade-long sexual relationship with her father, 60s musician John Phillips.

She appeared on The Oprah Winfrey show this week to talk about the affair and promote her new book, "High on Arrival. "

She was joined by her "One Day at a Time" costar and pal Valerie Bertinelli.

Usmagazine.com has now confirmed that Mac will be back on Oprah's show on Friday.

And she will be joined by her half-sister Chynna Phillips, who, by the way, has a brand new album to promote.

Nope, not making this up.

The buzz is that Mackenzie will appear via satellite on Friday; Chynna will be live in the studio,

Chynna has openly said that she believes her sister. But she also says the news sent her into a depression. "A part of me died when I found out."

Will you watch the show?

Wonder when Mackenzie's stepmom Michelle Phillips will be on Oprah's show to tell her side of the story? She's already denied Mackenzie's allegations and slammed her for soiling her father's legacy.

You know that's gotta be next week's show. This is getting better than Jerry Springer!

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