Acorn is one of the Pussywillow Pixies. As she is the youngest, Acorn often wants to prove she is as good as the other Pixies, and she proved it in "Babes In Wartland".
She and her fellow pixies first met the Smurfs when Clumsy was accidentally taken into the hollow by a deer crossing Toad River. With the Smurfs' help, Pansy freed her fellow pixies from the Wartmongers and continue to live in the hollow, meeting the Smurfs from time to time ever since.
Acorn was voiced by Patricia Parris.