Robert Anthony Rist is an American actor and voice artist. He is best known for his role as Cousin Oliver on The Brady Bunch, as well as Martin on Grady and Little John on Big John, Little John. Rist voiced Michelangelo in the original Teenage Mutant Ninja Turtles film trilogy (1990–1993) and later voiced Casey Jones in the 2011 installment. His extensive voice work also includes roles such as Stuffy in Doc McStuffins, Whiz in Kidd Video, Star in Balto, Maroda in Final Fantasy X, and Choji Akimichi in Naruto. He appeared as David, the adopted son of Ted and Georgette Baxter, on The Mary Tyler Moore Show, and was the voice of the stick figure in Handi Snacks commercials. Alongside director Anthony C. Ferrante, Rist also composed music for the Sharknado films, including the franchise's theme song.