Starting as a child actor, Robert Coogan made his film debut as Sooky in Skippy (1931), a comedy-drama family film which was nominated for an Academy Award for Best Picture. He also reprised the role of Sooky in its sequel Sooky (1931). In addition to his appearance in Skippy, Coogan appeared in over one dozen other films and made one appearance in a television production. Coogan continued acting in adulthood, but only with minor success. He also portrayed the role of Humphrey Pennyworth in the Joe Palooka B-movies.