Her mum was napping when the unthinkable happened.
Izzy LaPeruta, 7, was playing with a ball inside her New Jersey living room, next to a Christmas tree wrapped in colourful lights. She had bad aim, or the ball bounced, or ricocheted off the tree - who can be sure? - all that matters is that in the living room chaos, a little elf doll sitting in a red felt stocking plummeted onto the carpet.
If you're not familiar with Elf on the Shelf, the children's book that comes with a household elf, you might not understand what a catastrophe this would be for a 7-year-old who has high hopes for Christmas morning.
But Izzy understood. According to the book, this little leotard-wearing elf was sent by Santa to scope out who should be on the nice list. Every night, the elf flies back to the North Pole, and gives the big man a daily report.
If you want to keep your elf to keep up the good behavior reports, "There's only one rule that you have to follow, so I will come back and be here tomorrow," it says. "Please do not touch me. My magic might go, and Santa won't hear all I've seen or I know."