I bought them for a 3 year old and a 6 year old. Both of my girls are above average so I always go bigger and I did that for them too. The legs fit both of them perfectly, but the waist was a bit big. I ended up rolling my waist up once for both kids (similar to how you sometimes roll up your pants). They also have belt loops, so that's an option too if you run into this problem. Both of my girls ended up loving their new "jeans" and wanting to wear them non-stop all week.
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