Mousie Mona is a girl of unknown species (though she is presumed to be a duck).
This girl lives in Corona. She is an admirer of Donald Duck. On Christmas 1958, she wrote him a card, though Donald, too preoccupied with Roscoe the Reindeer, did not read it. Mousie may or may not be a relative of Donald's on top of an admirer.
Behind the scenesEdit
In the German localization by Erika Fuchs, "Mousie Mona from Corona" is replaced with "Aunt Betty from Brazil". Although the "Brazil" factoid contradicts the fact that Mousie comes from Corona, it is possible that Mousie Mona is indeed a relative, whom Huey, Dewey and Louie might call their "aunt".
Following on this notion, Johannes A. Grote's Duck Family Tree depicts Mousie Mona (or rather, this being a German effort, "Aunt Bettie") as both the sister of Drusilla Duck's husband and the daughter of Grandma Duck's Uncle Eider. For reasons detailed on the page about Drusilla's Husband, it would require a very unorthodox view of Daisy and Scrooge's parentage for both these things to be true at once; however, either could very well be.