A.O.
Let her "oversleep". Explain Santa came but we just couldn't wake you up! But he left this special card (gift Etc) and Hopes he can see you next year. Nothing Major but maybe a bell like in the Polar Express movie with a special letter. I know my girls would in no way get up at 4 am. Just a thought. I wouldn't try to go in to too much detail. She might lose the magic of Santa.