Size small (4-6) fits my 3 year old well. She is 39 inches tall and weighs 32 pounds. We have room to stretch, but the tights don't interfere and don't hang down her legs. I expect to be able to use this size for the next 9 months of dancing and maybe even next year. If they hold up I bought theater pink and it goes perfectly with her ballet leotard and shoes.
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