The Rubber Duck
One year for Christmas, Harry Potter gave Arthur Weasley the greatest gift of all, a rubber duck. Arthur had always been curious about the function of the rubber duck; such muggle inventions had captured his imagination for years. For a long while he sat and stared at the gift Harry had bestowed upon him. His intense fascination with this muggle invention irked Molly who had been pushed aside and neglected in his analysis of the rubber duck. For many weeks after Christmas Arthur "played" with the rubber duck. He threw it around, used spells on it, put it upside down and dangled it from the ceiling. None of these "games" involved water. After a game of Exploding Snap which burned the coffee table, Molly begged Harry to tell Arthur the true function of a rubber duck.
"Really, you just take a bath with it." Harry tried to explain, but Arthur could not accept the simple and seemingly useless function of the rubber duck.
"That seems ridiculous!" Arthur was outraged. How could Harry be trying to play a trick on him? After everything they had been through! "Fine then!" Arthur snapped. "I'll go take a bath with this and prove to you that that is not the function."
Arthur spent a long time in the bathroom. Harry and Molly sat on the sofa waiting for him to come out. Occasionally there was a squeal of delight from the washroom which interrupted the awkward silence that had fallen in the living room.
"I think he has the idea." Harry said after a while. "I think I'll head out now."
Molly gave him a hug goodbye and continued on doing... whatever it is Molly does. When Arthur finally emerged from the washroom with a huge smile on his Molly sighed deeply. How could she not help but love this insane man?