XS fits me and my 10 year old!
Verified Buyer Reviewed by Annb from colorado on Wednesday, October 7, 2015
These are great. Very stretchy and lightweight. I hope they keep us warm this winter while skiing, but boy are they comfortable! I am 5'3 and 117 (typically a size S) and these fit me and my slender 10 year old daughter who usually wheres a 10/12. She likes wearing them to bed. They are just a bit loose on her, but just a bit and she finds them more comfortable then other base layers she owns. I don't find them too tight for me either. We ordered 2 pairs, one for me and one for her.