Lisa complains to Marge that Homer never pays any attention to her or gets involved with her interests. Marge suggests that Lisa take an interest in something her father does, so she decides to join Homer on the couch while he is watching football on television. After being ripped off by betting advice hotlines, a desperate Homer turns to Lisa to pick a winner. She picks the Miami Dolphins, prompting Homer to call Moe's Tavern to place his $50 bet. In the end, the Dolphins win, and Homer and Lisa celebrate.
Meanwhile, Marge suggests that she and Bart have a Mother-Son day shopping for new clothes since Lisa is spending time with Homer. Bart claims he doesn't need new clothing, but it's seriously undermined when she sees how damaged his clothes are. At the mall, Marge's excessive mothering embarrasses him more when she buys clothes from the clearance rack and ignoring his disgust by making him try out the clothes she picked for him. Bart remains hiding in the car, while the bullies taunt him to come out and Marge takes no notice of believing the bullies to be his friends.
Lisa becomes adept at choosing winners of football games, and Homer declares every Sunday during football season Daddy-Daughter Day. Lisa remains perfect in her picks for eight weeks, earning her father more and more money as the Super Bowl approaches. With his new money, Homer starts buying expensive presents for the family and treating them to fine dining. When Lisa asks Homer if they can go hiking the Sunday following the Super Bowl, he tells her that he is instead going bowling with Barney and that Daddy-Daughter Days are over until next football season. Lisa realizes that all Homer really wanted was to exploit her prognostic abilities to help him gamble. She dreams that she grows up to become a chain-smoking, thrice-divorced, casino-hopper. Completely heartbroken, Lisa gives away all the toys Homer bought for her. At night, Marge berates Homer for using Lisa's gift for his own purposes.
Homer realizes he needs to make amends with Lisa, but she is too hurt to even talk with him. Homer briefly cheers her up by inviting her to watch the Super Bowl together, but shows that he still only wants to win a bet. Heartbroken, she agrees to tell Homer who she thinks the winner will be, but she fears that she may be so distraught that she subconsciously wants Homer to lose his bet, leading her to a cryptic prediction: if she still loves Homer, Washington will win; if she does not, Buffalo. Homer bets with Washington, while the others go with Buffalo. As a nervous Homer watches the game at Moe's Tavern, Washington scores at the last second to win the game. Homer becomes happy at this blessing and Bart tells Lisa that she still loves Homer, with which she agrees. Homer cancels his bowling date with Barney and—on the Sunday after the Super Bowl—makes good on his promise to go hiking with Lisa despite not being in good shape.