A Night at the Opera (film) DVD commentary. But this could not have occurred, because Sam Marx had died in 1933, during pre-production of "Duck Soup", two years before "A Night at the Opera" was released. The rumor arose because Frenchy had had such a cameo appearance in the Marx Brothers' earlier "Monkey Business". There is, however, a reference to the Marx Brothers' mother, Minnie Marx, during the stateroom scene, in which a woman asks, "Is my Aunt Minnie in here?" Part of the concept of casting the Marx Brothers as stowaways on a ship was recycled from "Monkey Business". As Groucho's and Margaret Dumont's characters
Marx Brothers appeared, sometimes with Chico and Zeppo caricatured, in cartoons starring Mickey Mouse, Flip the Frog and others. In the "Airwolf" episode 'Condemned', four anti-virus formulae for a deadly plague were named after the four Marx Brothers. In "All in the Family", Rob Reiner often did imitations of Groucho, and Sally Struthers dressed as Harpo in one episode in which she (as Gloria Stivic) and Rob (as Mike Stivic) were going to a Marx Brothers film festival, with Reiner dressing as Groucho. Gabe Kaplan did many Groucho imitations on his sit-com "Welcome Back, Kotter" and Robert Hegyes sometimes imitated both Chico