The surname of the family has been revealed only twice in the show. First, in the pilot episode, where Francis wears the name tag "Wilkerson" on his school uniform (it can be seen best in the scene where he is talking with his family on the phone). Also, although unaired, the name appears in a joke from the original pilot script. In that script, Malcolm was walking to school when a neighborhood kid came running up shouting, "Malcolm, Malcolm, Malcolm. I was talking to my parents last night - I was listening to them talk, and what's your last name?" "Wilkerson, why?" Malcolm replied. "Oh. Who are the Pariahs?" said the other kid. The joke was eventually cut. The last name, however, was spoken in the series finale when Malcolm is being introduced for his graduation speech, but it is not hear