No Teasing
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"No Teasing" was the first commercial for Nestle's Butterfinger featuring Bart, Lisa and Maggie which aired on October 1, 1988, while "The Simpsons" shorts were still running on The Tracey Ullman Show.
Plot
Bart comes into a room where Lisa and Maggie are and teases them for having the last Butterfinger stocked in the house. Lisa mentions to Bart that you're "dead meat" when someone screams, so Lisa screams for Homer, and immediately, Bart throws parts of his Butterfinger into Maggie and Lisa's mouths. After Homer asks what's going on, Maggie points at her mouth, as Bart looks sadly down at the remaining part of his Butterfinger.
Remake
A remake of the commercial aired on January 1, 2007, where Bart gets in trouble for taking a Butterfinger.