J. Randy Taraborrelli, author of Michael Jackson: The Magic, The Madness, The Whole Story, tells ET that he thinks Katherine Jackson will rely on one of her daughters to help raise the King of Pop’s three kids. Taraborrelli says he believes Michael's sister, Rebbie Jackson, will lend a hand. "Rebbie would sort of be the primary caregiver to Michael's children even though Katherine would have custody of the children," he tells ET. Michael's mother and his ex-wife Debbie Rowe negotiated an out-of-court agreement for custody of the late singer's children on Thursday.