My 3 year old could not wait to be Mickey Mouse for Halloween. The day we got this costume was such a disappointment!! We ordered the size Child S (4-6x). My son wears a size 4 or 5 in regular clothes. This costume was so snug (with only a t-shirt and underwear on) - and the hat was so small, my guess is it would only fit a baby. He wasn't happy, but we had to return it. So sad. I should have read the other reviews about the size discrepency before I ordered it.