Because of its many changes over the years, My Three Sons seemed almost like two different shows. Both were very good, but I prefer the earlier episodes, the black & white ones. They had a certain charm to them that was missing in later years. Robby somehow never seemed to fit the eldest brother role the way Mike did. That, and the move from Bryant Park, Michigan out to Los Angeles took away the small town feel that the earlier episodes had. Then came the arrival of women into the family, and that changed everything.
For the first five seasons, 1960-61 to 1964-65, the show was aired on ABC and filmed in black & white. For the last seven seasons, 1965-66 to 1971-72, it was aired on CBS and filmed in color. For the first 4.5 seasons, the boys "nanny" was their grandfather Bub, for the last 7.5 seasons it was their great uncle Charlie. For the first 5 seasons, the sons were Mike, Robby, and Chip, for the last 7 seasons the sons were Robby, Chip, and Ernie.
William Frawley left the show halfway through the 1964-65 due to ill health (he died in 1966). In the story line, Bub went over to Ireland to visit relatives and decided to stay there. Shortly after his departure, his brother Charlie arrived for a visit, and ended-up staying for the rest of the shows run. After the end of that season, Bub was never referred to again. In the first episode of the 1965-66 season, Mike married his girlfriend Sally and moved to another town to take a job. This marked Tim Considine's departure from the series. To re-establish the "three sons" storyline, Steve Douglas adopted Chip's friend Ernie, who had recently become an orphan. Mike was never seen again (not even when Steve married Barbara) and was only sporadically referred to thereafter.
More bits of trivia:
Before being cast as Katie, Tina Cole had appeared several years earlier(in the black & white days) as Ina, one of Robbys friends.
Stanley Livingston and Barry Livingston are brothers.
Before being adopted by the Douglases, Ernies last name was Thompson. Years later, Chip married Polly Thompson, no relation to Ernie.
When Robby and Katie had kids, it was triplets. They were all boys, thus keeping with the "three sons" theme.
Originally, the show was going to be called "The Fred MacMurray Show", but MacMurray objected to that, so the title was changed.
In its early years, My Three Sons was sponsored by Chevrolet, thus Chevy cars were seen behind the closing credits.
There are two syndication packages for My Three Sons. One package consists of the first five seasons (the black & white ones) and the final season. The other package contains the other six seasons. Why it is done this way I don't know, it doesn't make sense to me. I would think they would just have the B&W episodes as one package and the color episodes as the other.
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