I ordered Sz Small for my 5 year old. It's roomy, which is what I expected as she usually wears a size XS. I erred on the plus side to make sure it would fit. I didn't want a tight sweatshirt dress. This is probably pretty close to the exact size. This is now classed as a dress and while it is actually longer than a standard sweatshirt I would consider it more of a tunic than a dress. The length seems like a decent dress length for my daughter who is 3.5ft but keep in mind this is a size larger than she normally wears. It will look shorter on her once it fits her better. Whatever you call it, it's still cute and pairs well with leggings.
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