While at Moes, Homer finds an old roll of film in his jacket pocket that he never developed.
Carl tells him there aren't any places to get film developed anymore, but Moe says he can do it. The pictures are all of Bart and Lisa fighting, which makes them wonder why they fought so much and what made them stop.
Marge begins to tell them the story of when they began constantly fighting at a library.
Marge is losing sleep over their fighting and takes them to a therapist. She tells them that one child is smart and good and the other one is dumb and evil.
Ned invites Homer and Marge to brunch to give them some time away from the kids and says his mom can babysit.
Homer and Marge are late to brunch to spend alone time together while the kids are with the sitter. They return home from brunch to discover that Ned's mom is dead and Bart and Lisa are missing.
Bart runs into the bullies who are threatening him. Lisa arrives and fake cries to make the bullies feel bad and leave him alone.
Homer and Marge are worried about the kids and Homer goes out looking for them.
Bart pushes Lisa down a hill, but saves her before she crashes into a tree.
Homer and Marge finally find the kids sitting on top of a tire fire.