Anna Nicole Smith's Sister Spills Drug Secrets  4/16/07

Anna Nicole Smith was hooked on drugs 16 years before her death, according to her half-sister.

Donna Hogan reveals the late Playboy model took drugs Xanax and Vicodin to overcome the crippling pain caused by two breast enhancements.

In her new book, Train Wreck: The Life and Death of Anna Nicole Smith, Hogan says drugs and alcohol were the only form of relief for her sister.

She says, "Due to the extent of the increase in size, the extra weight of her breasts caused her all sorts of pain from her back to her neck to headaches to the pain of that added mass pulling at the tissue and pectoral glands - especially when she was not wearing any kind of support. She had to resort to medication."

The 39-year-old died after being found unconscious in her hotel room at the Seminole Hard Rock Hotel and Casino, Florida following a drug overdose in February (07).