Mackenzie Phillips on her 10-year incestuous relationship with dad John

Mackenzie Phillips is getting candid about her 10-year incestuous relationship with her father, the Mamas & the Papas frontman John Phillips.

The “One Day at a Time” actress appeared on her sister Chynna’s YouTube Channel on Wednesday where Chynna called their father “one of my favorite individuals in the whole wide world” but had a “dark” side.

“Talk about complex, so many different levels to who he was,” Chynna, who is married to Bill Baldwin, said. “Obviously he’s an amazing songwriter.”

“Genius,” Mackenzie agreed.

“I loved his laugh. Yet there was this whole other side to dad that was kind of, like, monster,” Chynna continued, to which Mackenzie also agreed with.

“He had a very dark side,’ Mackenzie said, with Chynna agreeing: ‘He was so dark, and you just didn’t know who you were going to get, right? it was very unpredictable.”

Mackenzie claimed in her 2009 memoir “High On Arrival,” that her father raped her on the night she married Jeff Sessler. She was 19 at the time.

But Mackenzie would go on to battle with a drug addiction and the sex with John became consensual for nearly 10 years.

The sisters on Wednesday were not interested in rehashing all the details of what happened between Mackenzie and their father, but Chynna once again took a moment to show Mackenzie support for speaking out about the unusual affair.

“When I stood by you, I meant it with all my heart,” Chynna before showing her 2009 appearance on “Good Morning America” where she spoke about the family’s bombshell secret.

“I believed you and I want you to know that I was proud of you for coming out, even though it was painful for everybody.”

Mackenzie, who has been married to composer Keith Levenson since 2005, continued that she faces backlash online for having “forgiveness in my heart” towards her father, who died on March 18, 2001, of heart failure.

“Forgiving is for me, not the other person. And forgiving doesn’t mean that I co-sign or agree with what I’m forgiving you for, or him for. It’s very complicated. It’s very, very complicated. And yet, I am at peace,” she revealed.