Santa's Little Helper is a novella written by Cathy East Dubowski. It was first published in 1997 and was the fifth book in the Sabrina the Teenage Witch book series.
Description[]
Christmas magic
Sabrina's down in the dumps. Everyone else has the holiday spirit...even Libby Chessler! Sabrina's aunts, Hilda and Zelda, are trying to give her a happy holiday, but their best spells fall flat. And Harvey seems so busy and secretive. Is he giving her the brush-off for Christmas? Sabrina decides to give him the ultimate Christmas gift: Elvis' voice for the holiday concert!
What a disaster! Suddenly Harvey's a chick magnet and Sabrina's out in the cold. Then, when she volunteers to take Jenny's place as Santa's elf, Santa and the presents disappear! It will take a miracle--or a teenage witch-- to save this Christmas. But can Sabrina succeed and keep her secret safe?