Jett was born in Philadelphia, PA; her family moved to Los Angeles when she was 12 years old. By the time she was 15, she had formed her first band and was performing around town. Kim Fowley, a Los Angeles record producer, discovered the band at one of their gigs and became their manager; soon, he renamed the all-female group the Runaways and secured them a contract with Mercury Records. The band released three albums that never had much commercial success in America, yet were very popular in Japan; the group were popular in both the Los Angeles hard-rock and punk scenes, which led to Jett's production of the Germs' first record, G.I. The Runaways group broke up in 1980 and Jett moved to New York to begin a solo career.
However in there she must have been in Rockville because she went to Richard Montgomery HS, a friend of mine was her history teacher and I have heard her interviewed and she spoke about being here. I doubt that she had a very typical childhood.