Prince Fenwick is a character who first appeared in the cartoon show episode "The Magic Rattle". Not to be confused with Fenwick Quarrel, the human ghost who haunts Quarrel Castle, Prince Fenwick is the infant child of the fairy queen Fauna, who along with his mother were being pursued by the evil fairy Falan, who is after the magic rattle that Fenwick possesses so that he could rule all of Fairyland and spread evil and mischief. She and her child escaped capture at the beginning of the story and hid themselves near the Smurf Village, where they encountered Greedy and Baby Smurf. After Fenwick and Baby Smurf had switched rattles, Falan captured the queen and her child and held them hostage inside his castle with her grandfather, only to find that the rattle Fenwick had was not the magic rattle. Fauna revealed that the magic rattle was switched with Baby Smurf's and flew to the Smurf Village to get the real magic rattle. However, Papa Smurf had coated the rattle with an anti-magic powder so that it would be rendered useless for at least one hour, giving Papa Smurf and some of his Smurfs enough time to reach Falan's castle. By the time he arrived, Papa Smurf saw that Fauna, Fenwick, and her grandfather were trapped on a pedestal ready to be plunged into a pit with a vicious sabertooth cat ready to devour them. Using the magic rattle, Papa Smurf managed to rescue them in mid-plunge and to free them of their bonds, destroying Falan's throne in the process. Falan swore vengeance as he watched the Smurfs and the fairies fly away to safety.
His only other appearance was in the cartoon show special "Smurfily Ever After", where he appeared as a guest of Woody and Laconia's wedding.