Now the fit is perfect- However there are two pics this one with a little girl blonde/ and a brunette toddler.  I didn't have a problem because I did call the manufacturer to ask a few questions.  This one is a different model number and is for LITTLE GIRLS and the other is TODDLER.  The XS for this one is the same as the LARGE for the little Brunnette which is 4-6.  Our daughter is quite slim at 7 she is 45 lbs and 47 inches and this fit perfect, goddaughter  5 and 2 inches shorter took the same but could have taken the medium for the other one, and size 12 took the medium 8-10.

This costume is strecthy and one of 5 found it a little itchy but nothing a tank top didn't fix