<Tr> <Th> Audio format </Th> <Td> Monaural </Td> </Tr> <Tr> <Th> Original release </Th> <Td> September 29, 1960 (1960 - 09 - 29)--April 13, 1972 (1972 - 04 - 13) </Td> </Tr> <P> My Three Sons is an American sitcom . The series ran from 1960 to 1965 on ABC, and moved to CBS until its end on April 13, 1972 . My Three Sons chronicles the life of widower and aeronautical engineer Steven Douglas (Fred MacMurray) as he raises his three sons . </P> <P> The series originally featured William Frawley as the boys' live - in maternal grandfather, William Michael Francis "Bub" O'Casey . William Demarest, playing Bub's brother, "Charley", replaced Frawley in 1965 due to Frawley's illness . In September 1965, eldest son Mike married, and his character was written out of the show . To keep the emphasis on "three sons", a new son named Ernie was adopted . In the program's final years, Steven Douglas remarried and adopted his new wife's young daughter Dorothy ("Dodie"). </P>

Who played the dad on my three sons