Miley Cyrus is writing her autobiography. Just how long can that book possibly be? The girl is only 15, after all. I really want to be there when she reads it at age 30. The book will focus on the 15-year-old’s road to fame, from growing up in Tennessee to navigating the spotlight as an international star, and how her family – especially mother Leticia – helps keep her grounded. People.com If Miley has any sense about her (which...