Francis (along with Chester and A.J.) was originally going to be in The Bored Identity but was scrapped for unknown reasons.
Interestingly, despite the fact that he is a scary bully, in his last major appearance (Manic Mom-Day) he befriended Timmy (although it was Mrs. Turner in Timmy's body in reality). They danced together like ballerinas in the school bus. His true last appearance was in the episode "Dad Overboard" where Crocker dropped an F rock on him. This way, he could be considered a redeemed villain.
His father is the only member of his family to appear.