The term 'Animal Crackers Brothers' refers to the Marx Brothers, a comedy act from the early 20th century. The Marx Brothers were a family of five siblings who performed in vaudeville, Broadway, and film. They were known for their slapstick comedy and witty dialogue. Groucho Marx was the most famous of the brothers, and he was known for his iconic mustache and cigar. The Marx Brothers were popular in the 1920s and 1930s, and their films are still enjoyed today.