The Robins

This Los Angeles vocal group were the forerunners of the Coasters. They began as the Four Bluebirds in 1947, then became the Robins. Ty Terrell, Billy Richards, Roy Richards, and Bobby Nunn were the original members, with Carl Gardner and Grady Chapman adding in 1954. In 1957, Gardner and Nunn departed to form the Coasters. The Robins had two R&B Top Ten hits. "If It's So Baby" was done with the Johnny Otis Band in 1950 for Savoy, while their best-known number, "Smokey Joe's Cafe", was recorded for the LA based SPARK label, as shown here in 1955.
Also compare to The Robins (11).