There's a scene in The Godfather the book, not the movie in which child abuse and pedophilia in Hollywood is ascribed to a character.
It's a side of Jack Woltz that's not shown in the movie.
The book was published in 1969, and was the first place I ever encountered the subject, when I read it as a teenager in the early '70s.
In “The Godfather Trilogy”, they did show a brief scene of Jack Woltz’s (John Marley) girlfriend that he kept at his mansion, who looked to be perhaps anywhere from 10-14, that Tom Hagen spotted.
I know the exact sentence you reference. It describes a young girl leaving the producer or directors' office after being raped, with "legs as unsteady as a newborn foal".