I am 5'5" and 122 lbs. After reading the reviews I ordered this in a large, ordinarily I wear a medium. I can wear it, but it is snug. I need these for work so I'm now ordering one in extra large. But it's just annoying that it runs SO small. The fabric and style are good, if you can just get one that fits.  I believe if you ordered a size small it would fit your child's Barbies.