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.
Seasons
Season 1
36 episodes
Sep 29, 1960
Season 2
36 episodes
Sep 28, 1961
Season 3
39 episodes
Sep 20, 1962
Season 4
37 episodes
Sep 19, 1963
Season 5
36 episodes
Sep 17, 1964
Season 6
32 episodes
Sep 16, 1965
Season 7
32 episodes
Sep 15, 1966
Season 8
30 episodes
Sep 9, 1967
Season 9
28 episodes
Sep 28, 1968
Season 10
26 episodes
Oct 4, 1969
Season 11
24 episodes
Sep 19, 1970
Season 12
24 episodes
Sep 13, 1971
