Billy is Troy McClure's assistant who appeared in "Lisa the Simpson", and "Bart the Mother". He was supposed to appear in more episodes but due to McClure's voice actor Phil Hartman's death, he was retired along with McClure. He is a child who appears in Troy McClure's educational films. He appears in the films "Birds: Our Fine Feathered Colleagues", and "In The Kitchen with DNA". He was voiced by Tress MacNeille. A similar child named Jimmy (who at one point McClure also calls Billy) appears in "The Meat Council Presents: 'Meat and You: Partners in Freedom'" in the episode, "Lisa the Vegetarian".
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