Stevie's one of the characters who came to mind earlier when I was listing sightings of characters with disabilities in fiction to blog about. That show isn't on anymore here, and for some reason Region 2 never got DVDs so alas I don't have the show to refer to or watch again, but I always liked Stevie; I felt he and his family were portrayed in a realistic way and he was there as Malcolm's best friend, not just as a Poor Little Poppet.
Master list? I don't know; there is a list of films featuring characters with disabilities here. I'd like to see the same for TV and books.
What I do have is a small but growing list of what I've termed "condition comics". I've got really into comics that are about realistic situations and people's lives, and I've managed to collect a handful of comics and graphic novels in which characters have experiences which could be relatable for chronically ill people - some stuff's autobiographical or fictionalised reality. There's also the odd one with a fictional disease used to explain an aspect of the human condition.