The description on this states that an XS is 3T, so I bought a S. The Small was too big. I then bought an XS and it fit with some wiggle room (it was not tight). I found this sizing on other Stelle products Size XS (Height: 35-40inch/Age: 3-4Y), Size S (Height: 39-44inch/Age: 4-5Y), Size M(Height: 45-50inch/Age: 6-7Y), Size L(Height: 50-54inch/Age: 7-8Y). I think it is more accurate. My girl is 39 inches and as I said the XS still had some room. The top is lined and the skirt is really light and flow-y.
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