In High on Arrival, she describes the moment she realized what they were doing was very wrong: "The Mamas & the Papas had several gigs in Hawaii, and Dad and I had adjoining rooms. But I don't think I went to my own room the whole time. Dad had brought tons of pills, and I found us some coke. We were lying in bed, in a stupor, when Dad said: 'We could just run away to a country where no one would look down on us. There are countries where this is an accepted practice. Maybe Fiji.' Then he said, 'We can take Bijou and Tam and Shane and raise them as our children.' My father was completely delusional. He was fantasizing about living with me, as man and wife, and raising my siblings, his children, as our children.
"The moment he tried to make it romantic, I had a visceral reaction. 'No,' I thought, 'We're going to hell for this.'"
At the time, Mackenzie was also in a relationship with another man, the father of her son, Shane. Mackenzie says her boyfriend had no idea what was going between her and her father.