In O. Henry's classic short story "The Gift of the Magi," he refers to Jim and Della Dillingham Young as two foolish children who unwisely sacrificed the greatest treasures of their house for each other. In the story, Jim and Della are extremely poor and struggle to make ends meet. Despite their small allowance, both spouses wish to give their partner a valuable, worthy gift. Della realizes that she can sell her beautiful, long hair for a significant amount of money and does so to acquire twenty dollars, which she uses to buy an expensive fob for Jim's prized family heirloom, his watch.
Similarly, Jim also sells his most valuable possession, which is his watch, to acquire enough money to purchase Della a worthy gift. Jim ends up selling his family heirloom and uses the money to buy an expensive set of combs. When Jim returns to his flat later that evening, both spouses discover that their gifts are useless, which is why O. Henry refers to them as "foolish children." Jim and Della failed to consider what each other would purchase and sacrificed their most prized possessions.
Despite being foolish, O. Henry also mentions that they were the wisest because they possessed the greatest gift of all, which is love. Although their gifts were useless, Jim and Della's willingness to sacrifice their most valuable possessions demonstrates their unconditional love, which means more than any material possession.