We ordered a medium size and it is too big for an 8 year old who normally wears a medium size. According to their size chart, the average size should be suitable for ages 8 to 11 (that's a big gap!). but I would say that leggings are more geared towards the end of that spectrum (for 10-11 year olds). However, if you like to sew, the waist should be corrected the most, as it is too high (reaches to the ribs).
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