“The three were still very young when their mother, who Tom Arnold said was an alcoholic, moved out. His mother abandoned the family when he was a child, and he and his siblings were raised by their father: As a child, Tom Arnold was diagnosed with autism. He had 2 siblings: a sister Lori and a brother Scott.

Arnold was born Thomas Duane Arnold in Ottumwa, Iowa, the son of Linda Kay (née Graham) and Jack Arnold.