Bo Baxter is the father of Buster Baxter and ex-husband of Bitzi. He is an airplane pilot. In "Arthur's Faraway Friend", Buster went traveling with him all around the world up until the first episode of season three, "Buster's Back". Currently he is the private pilot of a band that is on tour, Los Viajeros. He flies them around North America and a variety of other places.
Bo never had speaking appearances in Arthur, but he was voiced by Marcel Jeannin in the spin-off series Postcards from Buster.
Bo Baxter was formerly only seen wearing a pilot uniform that consists of a teal hat, a white long-sleeved top, teal pants with a belt buckle, and gray loafers. In his early appearances, he was originally shown as an older version of his son Buster and his face was generally hidden from view. He never talked in the series, however, he did show up in pictures.
In the pilot episode, "Postcards from Buster," he is redesigned to have glasses, long hair, slightly tanner skin/fur, a cleft chin, and a less round face.
In the spin-off series, his appearance changed drastically again with a very short brown buzz-cut and a different pair of glasses. It is unknown how long Buster spent traveling around with his father, or if Buster has traveled or will travel with his father again in the future.