In 1927, Williams married saxophonist John Overton Williams. She met him at a performance in Cleveland where he was leading his group, the Syncopators, and moved with him to Memphis, Tennessee. He assembled a band in Memphis, which included Williams on piano. In 1929, 19-year-old Williams assumed leadership of the Memphis band when her husband accepted an invitation to join Andy Kirk's band in Oklahoma City. Williams joined her husband in Oklahoma City but did not play with the band. The group, Andy Kirk's Twelve Clouds of Joy, moved to Tulsa, Oklahoma, where Williams, when she wasn't working as a musician, was employed transporting bodies for an undertaker. When the Clouds of Joy accepted a longstanding engagement in Kansas City, Missouri, Williams joined her husband and began sitting in with the band, as well as serving as its arranger and composer. She provided Kirk with such songs as "Froggy Bottom", "Walkin' and Swingin'", "Little Joe from Chicago", "Roll 'Em", and "Mary's Idea".
In 1942, Williams, who had divorced her husband, left the Twelve Clouds of Joy, returning again to Pittsburgh.