 Margarita Sierra

María Margarita Suárez Sierra (January 5, 1936 – September 6, 1963), better known as Margarita Sierra, was a Spanish-American singer, dancer, and actress perhaps best known for her supporting role as the nightclub-singing Cha Cha O'Brien on the early 1960s ABC/Warner Bros. television series, "Surfside 6", with Troy Donahue, Van Williams, Lee Patterson, and Diane McBain.Episodes of "Surfside 6" often featured Sierra singing, usually in English, but occasionally in Spanish.