Sidney Poitier's singing voice was dubbed by opera singer Robert McFerrin (father of pop singer, classical conductor and composer Bobby McFerrin). Sammy Davis Jr. sings and acts the role of Sportin' Life in the film, but for contractual reasons his vocals could not be used on the soundtrack album, so another legendary Sportin' Life, Cab Calloway, recorded his renditions of the songs for posterity, singing to the film's orchestral and choral tracks. The Gershwin family strongly disapproved ...[Read Story ]