Mackenzie Phillips opens up about her 10-year incestuous affair with her own FATHER, Mamas & Papas frontman John, in rare interview with her sister Chynna – revealing how she FORGAVE him after he ‘raped her’ at age 19

Mackenzie Phillips has opened up to sister Chynna about the decade-long incestuous affair she had with their father, The Mamas & the Papas frontman John, revealing how she eventually forgave him for raping her and turned the abuse into consensual relation.

The 64-year-old One Day At A Time star appeared on Chynna's YouTube channel where the couple discussed their tumultuous childhood and the trauma they carried from those experiences.

Mackenzie, the daughter of John and first wife Susan Stuart Adams, made a startling revelation in her 2009 memoir, High On Arrival, in which she claimed her father first raped her when she was 19 – the night before her wedding with Jeff Sessler.

But when her life began to spiral out of control on drugs, the sex became consensual for nearly a decade, she said.

Mackenzie claimed in her memoir that her father first raped her when she was 19, but when her life began to spiral out of control due to drugs, the sex became consensual. Pictured circa 1981

Describing her father as “dark,” Mackenzie also revealed that she was cheated on online because she “had forgiveness in her heart,” but that didn't mean she “signed or agreed with what I forgive.” .. before him.'

Chynna, whose mother was the frontman's second wife, Michelle, delved into the topic of their father, starting by saying that John was “one of my favorite individuals in the entire world.”

“Talk about complex, so many different levels of who he was,” the 55-year-old singer, who is married to Billy Baldwin, explained.

“Obviously he's a great songwriter,” said Chynna, who formed pop group Wilson Phillips, while Mackenzie added: “Genius.”

'I loved his smile. Yet there was a whole other side to Dad that was a little bit monstrous,” Chynna continued.

“He had a very dark side,” Mackenzie said, to which Chynna agreed: “He was so dark, and you just didn't know who you were going to get… it was very unpredictable.”

Chynna then addressed Mackenzie, who is now a substance abuse counselor, about the fallout from her sister making her affair with her father public.

“When I stood by you, I meant it with all my heart… and I believed you and I want you to know that I was proud of you for coming out even though it was painful for everyone,” said Chynna.

Mackenzie revealed she was trolled online because she “had forgiveness in her heart,” but that didn't mean she “co-signed or agreed with what I'm forgiving… him”

Chynna described her father as “one of my favorite individuals in the entire world,” but admitted he had a “dark” and a “monster” side. She is pictured here with her mother and John's second wife, Michelle, in 1987

Mackenzie pictured with her mother, Susan Stuart Adam, John's first wife

Mackenzie continued, “Dad was something else. And I get a lot of criticism and a lot of trolls online because I have forgiveness in my heart.

'Forgiveness is for me, not for the other person. And forgiveness does not mean that I co-sign or agree to what I am forgiving you or him for. It's very complicated. It's very, very complicated. And yet I am at peace with it.'

Following the shocking revelation, Mackenzie said her loved ones “took a long time, but we have come together as a family again.”

She also admitted that she felt “guilty” for speaking about the “circumstances of our childhood.”

Chynna replied, “Well, you gotta remember, we're in the top 10 most dysfunctional Hollywood families in America.”

“And was that in Rolling Stone?” Mackenzie asked as her sister laughed.

“And the Baldwins were number 10,” Chynna exclaimed.

“We were number two, the Kennedys were number one.”

Despite all their past hardships, the Phillips sisters continue to make headlines — with Chynna and Mackenzie's brother, Bijou, having a tough year after her estranged husband, Danny Masterson, was convicted of rape.

Masterson was sentenced to 30 years in prison this year and Bijou has filed for divorce

Despite all their past hardships, the Phillips sisters continue to make headlines. Chynna and Mackenzie's brother Bijou has had a tough year after her husband, Danny Masterson, was sentenced to 30 years in prison this year for rape.

Less than two weeks after his conviction, Bijou, who shares nine-year-old daughter Fianna with Masterson, filed for divorce.

Chynna spoke briefly about her “terribly painful few years,” which also included her 22-year-old son, Vance, being diagnosed with cancer and “the horrible incident” with her brother-in-law, Alec, who is charged with involuntary manslaughter for fatally shooting cameraman Halyna Hutchins on the set of his film Rust.

In October, New Mexico prosecutors announced they would present a case against Alec to a grand jury.

The actor's lawyer, Luke Nikas, called the decision “unfortunate” and said he planned to fight the case in court.