Donald Duck is a twin! His twin sister is named Della "Dumbella" Duck (Also referred to as Thelma Duck). She is the mother to Donald's mischievous triplet nephews Huey, Dewey & Louie. Donald's sister was first mentioned in the cartoon short Donald's Nephews (1938), in which she sent her sons to visit Donald. Although, originally Della was referred to Donald's cousin in the comic adaptation of the short, in Rosa's The Empire-Builder from Calisota, chapter 11 of the Eiser Award-winning comic book series The Life and Times of Scrooge McDuck she was labeled as Donald's twin sister.

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