The show ran for 138 episodes. Family Affair was created and produced by Don Fedderson, also known for My Three Sons.
William "Bill" Davis, originally of Terre Haute, Indiana, is a successful civil engineer who develops major projects all over the world. A wealthy bachelor, often dating socialites, he lives in a large Park Avenue apartment in Manhattan, and has a quintessential gentleman's gentleman, Mr. Giles French. However, his quiet lifestyle is turned upside-down when his two nieces and nephew move in.
Bill's brother Bob and sister-in-law Mary (née Patterson) had died in an automobile accident a year prior to the premiere episode. Their children, teen Cissy, and her young siblings, twins Buffy and Jody, had been dispersed among relatives in Terre Haute, but none wanted to continue raising the children, so they attempt to give the responsibility to Bill. "Uncle Bill" isn't keen on the idea at first, but becomes endeared by each of them. First Buffy comes along, followed by Jody, and finally Cissy. The most mortified by the situation is Mr. French, who effectively becomes the children's nanny, in addition to his valet duties. However as time passes they all become a family, albeit an accidental one.
When Sebastian Cabot became ill, Giles French's brother, Nigel "Niles" French (John Williams) was introduced, working for the Davis family for nine episodes in 1967 while Giles is said to be in England visiting the Queen. In the last season, Bill hires a part time housekeeper, Emily Turner (Nancy Walker) to assist Mr. French.
Various other characters are also seen regularly, including several acquaintances of Mr. French who are in service (most notably Miss Faversham (Heather Angel), colleagues of Bill, and friends of Cissy.
Bill Davis — Brian Keith
Giles French — Sebastian Cabot
Catherine “Cissy” Davis — Kathy Garver
Jonathan “Jody” Davis — Johnny Whitaker
Ava Elizabeth “Buffy” Davis — Anissa Jones
Miss Faversham (Mr. French’s friend) — Heather Angel
Nigel “Niles” French (Mr. French’s brother) — John Williams (1967)