Vaughn began her performing career at the age of three in 1981, singing at church. In 1988, at the age of nine, she sang "I'll Be There" on the popular talent-comeption show Star Search, winning junior vocalist champion and overall junior champion.
Vaughn began her acting career in 1988 playing the role of Alexandria DeWitt on 227, followed by roles in Thea, Hangin' with Mr. Cooper, and Roc.
She performed in the off-Broadway musical Mama, I Want to Sing! Part 3. In 1998, Vaughn was honored with an NAACP Image Award for Outstanding Supporting Actress in a Comedy Series for her performance in Moesha. In 1992, Vaughn released her first album, Countess, featuring a variety of songs, including dance music and urban ballads. She starred in (and sang the theme song for) the UPN sitcom, The Parkers.