What a brilliant casting move--the filmmakers got Nancy Walker to guest star as Sophia's sister Angela.
A Hollywood veteran perhaps best known for "McMillan & Wife" and "Rhoda", Walker is just as petite as Estelle Getty, creating a fun sight gag and a perfect match (and perfect foe!) for Sophia. They buried Walker under the same makeup, wig, and glasses as Getty, but her distinctive voice is quickly recognizable.
Angela proves just like Sophia in other ways--namely, being stubborn and vindictive! Dorothy brings her over from Italy as a surprise present for Sophia's birthday, but old grudges surface. Will the reunion be a disaster?
Walker is excellent. Also, in a fun early plotline, Dorothy (amazingly) entrusts Rose not to reveal the surprise present too early, and your knuckles will get white as Sophia tries to trick Rose into doing just that!