Sylvester was identified as a musical prodigy. By the time he was seven, Sylvester had already become proficient on the keyboards, and by the age of eleven, he had mastered the guitar, bass, and drums as well. While still in high school, Sylvester had settled primarily on the guitar and joined a number of high school bands. One of these was the Viscaynes, a doo-wop group in which Sylvester and his friend Frank Arellano—who was Filipino—were the only non-white members. The fact that the group was integrated made the Viscaynes "hip" in the eyes of their audiences, and would later inspire Sylvester's idea of the multicultural Family Stone. The Viscaynes released a few local singles, including "Yellow Moon" and "Stop What You Are"; during the same period, Sylvester also recorded a few solo singles under the name Danny Stewart. With his brother, Fred, he formed several short-lived groups, like the Stewart Bros.