Born in Corona, California, Lewis grew up singing in her father's church. In 1984, at age 15, she auditioned for a children's musical called Hi Tops, written and produced by Ernie and Debbie Rettino, creators of Psalty, the Singing Song Book. Lewis passed the audition, and was able to go into the studio and participate in the soundtrack recording, with the rest of the cast members. While working with the musical, Lewis met a member of the rockabilly band, The Lifters. After becoming friends with the band members, Lewis was asked to join. Soon after, the band changed its name to Wild Blue Yonder. In 1992, Crystal worked in the sketch comedy television series Roundhouse, that aired on Nickelodeon.
Lewis previously lived in Montana with then-husband Brian Ray, with whom she has two children, who were homeschooled. Lewis and Ray divorced after 28 years of marriage, and she now lives in California. Her daughter, Isabella (Izzi Ray), is also a singer/songwriter, and released her self-titled debut album on February 12, 2012, followed by her remixes EP on October 22, 2013. Her son Solomon is also pursuing a career in music, having produced his mother's 2011 release Plain and Simple.