Bijou Phillips slams half-sister Mackenzie for incest rape allegations in new book High on Arrival.

Although Bijou had previously admitted MacKenzie had told her about her affair with dad John Phillips, who died in 2001, she took to her Twitter page in a series of tersely worded denouncements.

"Exploiting the history of our family and the death of our father John Phillips for the release of a book is disgusting,' Bijou Tweet-ed.

"Allegations of sexual abuse are not only hurtful, but malicious when he is not here to defend himself.

"When I was young my sister told me about this - it ruined my life and my relationship with my father.

"Up till that point, I was a normal kid. I got good grades, loved my horse, was pretty innocent. I moved out to NYC at 13. Started doing drugs, did not talk to my Dad anymore. I was deeply f**ked up.

"I'm 29 now, I've talked to everyone who was around during that time, I've asked the hard questions. I do not believe my sister. Our father is many things, this is not one of them.

"My dad and I made up when I was 20, a year before he died.

"I'm sad I lost those years with him, and I lost those years at home."