Aaliyah always worked alone.
Aaliyah . At the age of 10 , she appeared on the television show Star Search and performed in concert alongside Gladys Knight . Hankerson introduced her to R. Kelly , who became her mentor , as well as lead songwriter and producer of her debut album , Age Ai n't Nothing but a Number . Aaliyah worked with record producers Timbaland and Missy Elliott for her second album , One in a Million , which sold 3 million copies in the United States and over eight million copies worldwide .