Chip Off The Ol' Block

While Mom relaxes in a hammock near a pile of freshly raked leaves, Baby mows the lawn. One of the blades of the lawn mower hits a brick, however, and prevents Baby from continuing her task. She bends down and tries to remove the brick while the lawnmower is still running, but luckily Mom sees this and rescues Baby before anything bad happens. Mom places Baby on the hammock, removes the brick from the lawn mower, and proceeds to mow the lawn herself.

Mom eventually comes upon broken glass and syringe needles in the yard, which she unknowingly runs over with the lawn mower. The debris that flies out from under the lawn mower cuts into Baby's skull, killing her and knocking her body off of the hammock. Mom then walks up, raking a few loose leaves into the nearby pile. She lights his pipe and throws the lit match into the pile of leaves, setting it ablaze. A gust of wind reveals that Baby's body lay hidden beneath the pile.

Trivia

 * 1) According to storyboards and commentary, the episode was originally going to end with Mom noticing Baby's death and intentionally burning her body. Feeling this was too morbid, the creators changed the ending to Mom accidentally setting Baby's body on fire.