Bart trades places with a rich boy named Simon who looks just like him, but he discovers that Simon's half-siblings are planning to do him in to get his inheritance.

!! Tropes:

* BrickJoke: When Mr. Burns tells about his siblings and their early deaths, he mentions that most of them died from eating poisoned potatoes. In a later scene, Queenly offers her brother a potato.
* PrinceAndPauper: Bart and Simon
* TheResenter: Simon says his half-siblings Devon and Queenly resent him because their father left their mother to marry Simon's.
* SpoiledBrat: Queenly is upset for being given a car that isn't the same one she wanted and rants that it was her worst MartinLutherKing day ever.
* WeWantOurJerkBack: Albeit Lisa was reluctant to admit it to Simon.
* WouldHitAGirl: When Lisa hit Simon, she told him Bart would have hit her back in retaliation.
* WouldntHitAGirl: It came as a shock to Simon that Bart would.
* YoungestChildWins: Mr. Burns is his parents' youngest child and inherited their fortune because his siblings had premature deaths.