From Wikipedia, the free encyclopedia. Roy Frank “RJ” Mitte III (born August 21, 1992) is an American actor best known for his role as Walter White Jr. on the AMC television series, Breaking Bad. Mitte moved to Hollywood in 2006, and began training with personal talent manager Addison Witt. Mitte has mild cerebral palsy. His manager states that it was Mitte's diligence and attitude that has helped him overcome challenges in all areas of his life. Description above from the Wikipedia article RJ Mitte, licensed under CC-BY-SA, full list of contributors on Wikipedia.