Huey, Dewey, and Louie
In "Some Heir Over the Rainbow" by Carl Barks, Huey, Dewey, and Louie, along with Donald Duck and Gladstone Gander, are tested by Scrooge McDuck, who wants to pick an heir to his fortune. Using the legend of a pot of gold at the end of a rainbow, Scrooge secretly gives US$3,000 (One thousand to Huey, Dewey, and Louie, another for Gladstone, and the last one for Donald). Donald uses his money for a down payment of a new car, now being $1,000 in debt. Gladstone, considering himself too lucky to need the money this soon, hides the money for when and if he needs it, causing Scrooge to consider him a better option than Donald. Huey, Dewey, and Louie lend their money to a man who claims to need the money to search for a treasure. Initially thinking they were tricked out of the money, Scrooge actually considers leaving his fortune to Gladstone, even though he sees that as "an awful injustice to the world", but the man actually finds the treasure and pays the kids back. Scrooge makes Huey, Dewey, and Louie his heirs. Although this is disregarded in a number of later comics, it seems to be the most solidly canon indication of Scrooge's plans.