After Lisa's new pet guinea pig destroys the Simpsons' living room art, Marge falls in love with a beautiful painting at the Van Houten's yard sale, which Homer snaps up for 20 bucks. But, when Lisa reveals it's by a famous early 20th century painter and could be worth $100,000, Marge and Homer face a dilemma: split the money with the Van Houtens, or keep the cash as a "cushion" for their kids.