During this time, Main shuttled back and forth between Universal Studios and MGM. She appeared in several Metro musicals during the 1940s and early 1950s, including, "Meet Me in St. Louis" (1944) and "The Belle of New York" (1952). She played Mrs. Wrenley in the studio's all-star film "It's a Big Country" (1951). Main played her last roles for MGM as Mrs. Hittaway in "The Long, Long Trailer" (1954) and as Jane Dunstock in "Rose Marie" (1954). Main's performance as the widow Hudspeth in the hit film "Friendly Persuasion" (1956) was well-received, earning her a Golden Globe nomination for Best Supporting Actress.. Main's final film appearance was in her best-known role as Ma Kettle in "The Kettles on Old MacDonald's Farm" (1957)