Eight is no longer enough in the show's fifth and final season. First up, Susan's (Susan Richardson) and Merle's (Brian Patrick Clarke) baby girl raises the stakes in And Baby Makes Nine, then a young Ralph Macchio takes it all the way to ten, joining the clan as Abby's nephew Jeremy. Tom (Dick van Patten) and Abby (Betty Buckley) have their hands full running their bursting household as they gear up for their fifth anniversary, as life keeps throwing the curveballs. David's (Grant Goodeve) and Janet's (Joan Prather) union goes asunder, Nancy's (Diane Kay) modeling career takes off, and Tommy (Willie Aames) gets serious about love: as in marriage! Meanwhile, Nicholas (Adam Rich) gets a horse, Joanie (Laurie Walters) goes undercover video dating, and Elizabeth (Connie Needham) falls for a friend and one of Mary's (Lani O'Grady) patients falls for her. But when Jeremy's father returns, the clan's happiness is threatened.