HIGH SCHOOL MUSICAL star Ashley Tisdale is hiding a family secret from her fans - her aunt is serving a 10-year prison sentence for drug trafficking. Peggy Tisdale, 45, was locked up in 2005 after she was found guilty of five drug charges. The crimes were the latest in a long list of legal woes, including felony convictions for possession of firearms and battery of a law enforcement officer. But a publicist for the 22-year-old actress insists Aunt Peggy isn't really part of the Tisdale family, explaining her brother, the singer/actress' father Mike, hasn't spoken to his troubled sibling in more than 20 years. And Tisdale's grandfather, Henry, claims the star has never met her incarcerated aunt. However, U.S. tabloid the Star reports Peggy has attempted to cash in on her famous niece from behind bars - by requesting signed publicity pictures to sell on to fellow inmates.