In pre-World War II Mickey children's books (not comics) produced by the Disney studio, the nephews were usually called Morty and Monty rather than Morty and Ferdie. Very early books contain three or more nephews with various names, including Maisie and Marmaduke. Morty's name, short for Mortimer, is possibly in reference to the original planned name for Mickey, Mortimer Mouse, and Ferdie (sometimes misspelled "Ferdy") is short for "Ferdinand." Morty should not be confused with Mickey's ofttimes rival of the same name, or Minnie's wealthy rancher Uncle Mortimer.