Born Marie Marguerita Guadalupe Teresa Estela Bolado Castilla y O'Donnell, she began dancing professionally at age nine, receiving coaching from Eduardo Cansino, Rita Hayworth's father. Her uncle was Xavier Cugat, and she appeared with his band in Mexican nightclubs and traveled with them to New York; as their dancer, she helped the band in its triumphant introduction of the rumba to America. She began appearing on Broadway and in films in 1934. She danced in two or three of her films, but otherwise was usually cast as a tragic character. Somewhat busy as a screen actress from 1934-44, her film appearances afterwards were sporadic; altogether, she appeared in only 15 films. From 1937-40 Margo was married to actor Francis Lederer. From 1945 she was married to actor Eddie Albert; she was the mother of actor Edward Albert. In 1974 she was appointed Commissioner of Social Services for Los Angeles.