As Phyllis's daughter, Lisa Gerritsen established her importance to The Mary Tyler Moore Show in its very first episode. Though she returned only sporadically for the next few years, she was memorable playing an off-beat, brainy, talented little girl. In the premiere episode, test audiences didn't like Rhoda, played by Valerie Harper. Harper eventually became one of the most popular stars on TV, but her initial change from antagonist of Mary (which the audience disliked, since Mary Tyler Moore was universally loved by viewers) occurred because of Bess (Gerritsen). Because Bess likes Rhoda and thinks she's funny, to the eternal consternation of Phyllis, the audience changed their opinion of her too, and by the second episode she was Mary's best friend. Gerritsen returned in the role in the spin-off series Phyllis (1975–1977).