This episode is similar to a old Donald Duck short where Donald plays a trick on the nephews by making them think he has become a baby thanks to the fountain of youth, difference is, in this case, it's not a trick, he really is aging backwards
The title was originally going to be "The Yolk's on You".
Can't take a Yolk:
Is a pun of the old saying,Can't take a joke.
Donald in his younger years is what he looked like when he first starred in the wise little hen. Even his actions are exactly the same, and his practical jokes. Maybe the writers wanted to pay homage to the classic original Donald Duck.