Penny Marshall
Garry Marshall, creator and then part-time writer for "Happy Days", cast Marshall and Cindy Williams to guest on an episode of the show. The installment, titled "A Date with Fonzie", aired on November 11, 1975 and introduced the characters Laverne DeFazio and Shirley Feeney (played by Marshall and Williams, respectively). In that episode, Laverne and Shirley were a pair of wisecracking brewery workers who were dates for Fonzie (Henry Winkler) and Richie (Ron Howard). The pair were such a hit with the studio audience that Garry Marshall decided to co-create and star them in a successful spinoff, "Laverne & Shirley" (1976–1983). The characters of Laverne and Shirley appeared in five more episodes of "Happy Days". In 1982 at the beginning of "Laverne & Shirley"s eighth season, Williams left the show due to her pregnancy. Marshall continued with the show, but it was canceled after the season's final episode aired in May 1983.
Howard Cunningham (Happy Days character)
Howard C. Cunningham is a fictional character played by Tom Bosley on the sitcom "Happy Days," Actor Harold Gould played the character in the pilot, which aired as an episode of the anthology series "Love, American Style"). He is the husband of Marion Cunningham, and the father of Chuck, Richie, and Joanie Cunningham. Originally, Gould was supposed to reprise his role on Happy Days as Howard Cunningham but wanted to commit to something else so Bosley was offered the part. Howard is one of only two characters, the other being Fonzie, to appear in all 255 episodes of "Happy Days" and to remain with the rest of the cast for all 11 seasons; of the two, Howard is the only one to have also appeared in the pilot.