I ordered the same size as the boot and was so disappointed that I could barely get my foot into them. This product is amazing, best of all I can go almost 5 days without needing to recharge the battery. So I had to go to a hardware store and look for a screw that is the same size only to find out that they dont carry screws with the same head. It was very uncomfortable and I knew just after trying them on that I would have to return them. We had to return unfortunately. I got them the biggest size (my 4yr old is the same size as my 6yr old) and I’m sad that I can’t order them a size when the time comes. Was worried about receiving a defective or low quality product based on the mixed reviews I read but I happen to be in love with these slippers, they are cute and comfy. Sound quality is also amazing for this price range. Very comfortable, great value for the money! However, I would still buy again because it was exactly what I wanted for a decent price.