Like Casper the Friendly Ghost and Hot Stuff the Little Devil, Wendy is an opposite-type character, a girl witch who does good deeds.

Unlike Wendy, her aunts have green wartish skin of the type associated with Halloween witches.

[3] Like many of Harvey's stable, Wendy is a design variation on the prototype of Casper and so are Richie Rich, Gloria Glad, Little Dot and others.

Wendy made her first screen appearance in the theatrical Paramount Casper cartoon short, Which is Witch (1958).

Christina Ricci's character of Kat in Universal's Casper film was originally named Wendy in the script, but to avoid having to purchase the rights to the Wendy character, the name was changed at the last minute.