This is perfect for a cosplay if you don't have the time or want to make one yourself.

My daughter wears size 10/12 and the adult small fit her just fine. About 2 inches shorter than the size chart, boots will cover up anyways.

Bought the small size for my 9 yr old. The only downside is that it doesn't come in child sizes. We pinned the top and belt to fit her properly and didn't use the pants. Other than the size issue (which I knew I would have before purchasing) everything is as expected from a costume. She absolutely loves it.