Little Walter Bushey is the son of Samantha and Phil Bushey, and a resident of Chester's Mill, Maine. He is named after the harmonica player Marion "Little" Walter Jacobs. His legal first name is "Little," while "Walter" is his middle name.

Abandoned due to his mother's suicide and his father's insanity, Little Walter remained in the care of the hospital's nurses, including after the exodus from Catherine Russell Hospital. Despite (or perhaps because of) his parents' drug usage, Little Walter survives the massive explosion that poisons the air under the Dome.