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
as Steve Douglas
Don Grady
as Robbie Douglas
Barry Livingston
as Ernie Thompson
Stanley Livingston
as Chip Douglas
William Demarest
as Charley O'Casey
Beverly Garland
as Barbara
Tina Cole
as Katie
Dawn Lyn
as Dodie Harper Douglas
