A TV series is considered to be a "spinoff" when one or more of its regular characters were taken from the cast of a previous series.

In 1986, ABC premiered ‘Perfect Strangers,’ a sitcom about Midwesterner Larry Appleton and his distant European cousin Balki Bartokomous. Both got jobs at the Chicago Chronicle newspaper, where a woman named Harriette Winslow worked as the elevator operator.

Harriette, played by Jo Marie Payton, appeared on the show for just two seasons, but was so popular with audiences that the ‘Perfect Strangers’ team developed a spinoff about her and her family.

‘Family Matters’ revolved around the Winslow family, a middle-class Black family living in Chicago, Illinois. The series premiered on ABC in 1989 and quickly became a hit, thanks in no small part to a character named Steve Urkel, who was introduced midway through the first season. Urkel (Jaleel White) was the Winslows' nerdy neighbor, who annoyed Harriette's husband, Carl (Reginald VelJohnson), and tried unsuccessfully to woo the couple's oldest daughter, Laura (Kellie Shanygne Williams). The Winslow’s also had a son, Eddie, and a younger daughter, Judy.

The sitcom ran for nine seasons until 1998, and was a mainstay of ABC's popular ‘TGIF’ (Thank Goodness It’s Friday) lineup.

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