The Simpsons Season 10 Episode 3 - Bart the Mother Episode Description: Nelson invites Bart over to test a BB gun he "won" at an arcade center. When Bart uses it and accidentally kills a bird mother, Marge becomes furious with him, thinking that he killed the animal on purpose. Bart feels guilty for what he has done and takes it upon himself to nurse the mother's orphaned eggs. Marge soon finds out about this and becomes proud of him. However, when the eggs hatch, they are found to be lizards that lived in the bird's nest. Skinner, a member of the Springfield Birdwatching Society, tells Bart that the lizards must die because they kill so many species of birds. Bart refuses and helps the lizards escape. After the lizards devour the pigeon population, which the townsfolk considered to be a nuisance, Bart is honored by Mayor Quimby.