OK, Lisa discovers a talent in solving crosswords, and enters tournaments. Homer starts betting for her to win, and when she does, he wins money. But in the final part of a tournament, Homer bets against his daughter. The opponent wins by tricking Lisa, and so Homer won. But then Lisa finds out, and is heartbroken her father would bet against her. Homer tries to cheer her up, but it seems nothing will work. So Homer gets to make the crossword clues arrange and be a message of apology for Lisa. They make up.
There was some humor in it, but I really cannot hold a straight face when people say the ending was sad. It was tacked on and forced, not sad