<P> Dee Thomas (Danielle Spencer) is Raj's younger sibling . She personifies the typical "annoying little sister ." She is bratty, keen, shrewd, and obsessed with making money, usually by blackmailing her brother and his friends a quarter at a time . As the series progressed and Dee grew older, her caustic personality mellowed into a sly sense of sarcasm . While Dee still enjoyed scamming Raj out of a quarter every so often, she became more likable and got along better with him . After Raj moved into an apartment in the third season, Dee remained in the Thomas house with waitress Shirley moving in to help out . Her trademark phrase is "Ooooohh, I'm tellin' Mama!" or "Ooooohh, you're gonna get it!" when she witnesses or hears about a wrongdoing, especially by her brother . Her favorite food is peanut butter . Her birthday is September 17 . </P> <P> Shirley Wilson (Shirley Hemphill) is a portly waitress at the neighborhood restaurant Rob's Place, where the main cast is regular patrons . She is a brash person who likes to take shots at the boys, and most often clashes with Rerun (with both Shirley and Rerun being overweight, they exchange "fat jokes"). Some episodes turn the spotlight briefly on Shirley and her joys and sorrows . Shirley moves into the Thomas residence in the last season to be a guardian to Dee after Raj moves out and Mrs. Thomas leaves to tend to a sick relative . </P> <P> Bill Thomas (Thalmus Rasulala) is Mabel's ex-husband and the father of Roger and Dee . He divorced Mabel, ran out on his family, and became a shady character . When he first appears, he tries to con Mabel out of money . Later episodes in which he appears depict him in a more positive light and culminate with his marriage to Lee Henderson (Lee Chamberlin). After his marriage, Bill was never seen again on the show, although he is mentioned . On follow - up series What's Happening Now!!, he guest starred in that show's Season 2 premiere episode "Nadine's Surprise". In that particular episode, it was explained that him and Roger had a strained relationship since he remarried and the latter's wife Nadine had planned a surprise reunion because Bill was planning to make amends with his estranged son . </P> <P> Gene "Rabbit" Walker (Ray Vitte) is a political - science major at the University of Southern California, and a track - team member . He appears in two first - season episodes as a boarder at the Thomas home, renting Dee's bedroom . In his first appearance, he is referred to as "Dean" which is even written on the end credits . Gene took a liking to Dee, giving her the nickname "Small Portion". In another episode his character is mentioned as being away (although his name was not given) so Mrs. Thomas offered his room to Dee's ex-con pen - pal . </P>

Who played the father on what's happening