It's Christmas Eve and mom is busily preparing the last minute decorations in the family room when little Sally asks: "Mom, don't forget to put out the treat for Santa next to the fireplace."
The mom thanks Sally and goes to the kitchen for Santa's treat. Later, when putting her to bed Sally says. "Mom, why did you put a can of Slim-fast next to Santa's treat?"
Distracted and anxious to get back downstairs to finish the decorations mom replies. "Daddy is on a diet."