A widower and aeronautical engineer named Steven Douglas raises three sons with the help of his father-in-law, and later the boys' great-uncle. An adopted son, a stepdaughter, wives, and another generation of sons join the loving family in later seasons.
Fred MacMurray
Steve Douglas
Don Grady
Robbie Douglas
Stanley Livingston
Chip Douglas
Barry Livingston
Ernie Thompson
William Demarest
Charley O'Casey
Beverly Garland
Barbara
Tina Cole
Katie
Dawn Lyn
Dodie Harper Douglas
