Santa's Little Helper and is the center of the plots of several episodes. During the course of the show, he has fathered litters of puppies, passed obedience school, had surgery for bloat, replaced Duffman as the mascot for Duff Beer, and been trained as a police dog at Springfield's Animal Police Academy. Some of the episodes that focus on Santa's Little Helper have been inspired by popular culture or real experiences that staff members of the show have gone through. Although cartoon animals are often anthropomorphized, Santa's Little Helper generally exhibits canine behavior. Cast member Dan Castellaneta currently provides the dog's sounds on
The Simpsons episode guides the 2003 episode "Today I Am a Clown", where Lisa uses it to remind Homer that Santa's Little Helper was supposedly neutered in a previous episode (specifically, "Two Dozen and One Greyhounds"). The guide provides an episode-by-episode history of the first eight seasons of "The Simpsons". Each episode is covered in either one or two pages, featuring a synopsis, credits, pictures, and memorable quotes, as well as the episode's chalkboard gag. Obscure or hidden jokes are also brought to attention. The episodes are arranged in chronological order, and at the beginning of each season are two-page special features, such as