LOS ANGELES — For six seasons on her '90s daytime talk show, Rosie O'Donnell spoke openly about the struggles associated with her childhood. At the age of 10, she lost her mom Roseann to breast cancer, which shaped the rest of her life.

In an upcoming book, "Ladies Who Punch: The Explosive Inside Story of 'The View'" by Variety's New York bureau chief Ramin Setoodeh, O'Donnell talks publicly for the first time about another dark aspect of her youth.

O'Donnell says she was sexually abused by her father, Edward Joseph. "It started very young," O'Donnell tells Setoodeh. "And then when my mother died, it sort of ended in a weird way, because then he was with these five children to take care of. On the whole, it's not something I like to talk about. Of course, it changes everyone. Any child who is put in that position, especially by someone in the family, you feel completely powerless and stuck, because the person you would tell is the person doing it."

O'Donnell's father died in 2015.

Although she hadn't told her story until now, O'Donnell has been a longtime advocate for sexual abuse victims, speaking out against alleged sexual predators such as Bill Cosby and Roman Polanski. O'Donnell was one of the first public figures to say she believed Dylan Farrow, who in 2014 published an open letter in the New York Times with allegations that her father, Woody Allen, sexually assaulted her at the age of 7. "I'm very anti-Roman Polanski and anti-Woody Allen," O'Donnell says in the book. "It's a pretty clear line for me."

The details about her father appear in a chapter about "The Rosie O'Donnell Show," which aired from 1996 to 2002, and changed the daytime TV landscape with its focus on celebrity interviews and pop culture. O'Donnell later became more political when she appeared on "The View" for almost two seasons. She replaced Meredith Vieira as the show's moderator for one year in 2006-07. She re-joined the cast in September 2014 for six months after creator Barbara Walters retired.

"Ladies Who Punch" will be published by St. Martin's Press on April 2.