Frankie Jonas (born September 28, 2000) is an American actor who was a voice actor in the film Ponyo and a recurring character in the television series Jonas. Frankie is the son of Denise and Paul Kevin Jonas Sr. and the younger brother of Kevin Jonas, Joe Jonas and Nick Jonas. Jonas is sometimes referred to as the "Bonus Jonas" and ''Biff''. He is of Italian (from a maternal great-grandfather), German, Cherokee, English, Irish, Scottish, and French-Canadian descent. In 2009, Jonas voice acted in Hayao Miyazaki's animated film Ponyo, released in American theaters on August 14, 2009. He played Sōsuke, a character who is befriended by a juvenile fish named Ponyo (voiced by Noah Cyrus), who wants to become a human girl. They also both sing the theme song of the movie.