Danny Mummert (1934–1974). Made his debut as pesky neighbor kid, Alvin, in the first "Blondie" movie,1938. He grew up in the "Blondie" series until 1950. After the series ended, he played several teenage roles, retiring from film in 1952 except for occasional guest spots. His personal life after his movie career was unhappy. He worked as a TV film producer, a screenwriter, and in advertising. He married 4 times. On the day before his last divorce was finalized, he shot himself to death.