Old Refrigerator - The plug in is looking bad perhaps?

If you believe they will want to use the refrigerator, then leave the door open. i am uming the kids from the day care are not coming to your house while your parents are gone, otherwise I would not give this advice. With the fridge unplugged there is no circulation inside and it will definitely develop a bad smell over a couple of days. So prop the door open and leave it unplugged until they get home.