Buster Baxter is a fictional eight-year old American bunny rabbit who is best known for being the supporting character in the Marc Brown books and the PBS television series Arthur, and the protagonist of its spin-off, Postcards from Buster.
Buster is a anthropomorphic white rabbit. He is usually shown wearing a light blue sweater with a salmon colored collar and blue jeans. In episodes involving sleepovers, when Arthur is shown wearing bunny slippers, Buster is shown wearing Arthur slippers.
Buster is Arthur's best friend. They are classmates in Mr. Ratburn's third-grade class (and classmates in second grade and kindergarten as well in flashbacks), and both share an interest in the Bionic Bunny and Dark Bunny comic books, among other things. Buster is usually jolly and upbeat, and likes watching television, reading comic and joke books, playing the tuba, and eating (Many of the remnants of his food conquests are in his food collection). Despite his insatiable appetite, he is still fit because he exercises as much as his friends. Buster is usually disinterested in schoolwork, and has had trouble passing into the fourth grade and even finishing a whole book. He also has asthma. Buster is a strong believer in aliens and wacky superstition theories.
In many shows, Buster serves as a character foil for Arthur's friend The Brain, who is smart and well-groomed much as Buster is dumb and sloppy. A recurring story arc is for Buster to try and state that his superstitions are better than Brain's science. Buster has acted as a detective on occasion, once teaming up with Fern, and is usually successful, though his tendency to embrace superstition and conspiracy theories (for example, blaming crimes on mutant mole people) hinders him.
Buster was absent from the show for much of season 2 when he was traveling with his dad, Bo. His parents are divorced and he lives with his mother, although he occasionally travels with his father, who is a pilot. He suffered from asthma, likes to tell jokes, sometimes seems to be obsessed with aliens and stars in a spin-off series called Postcards from Buster. Buster Baxter also plays his tuba in the band. Buster had a brief leave of absence from the middle to the end of Season 2 as he went touring with his dad but returned at the start of Season 3.