This shirt just like this brand runs very small! I know these are supposed to be fitted but my 6mo fits into 18 months size - granted it is a little loose but not by much!  As other reviewers have stated it is very very short - and rides up a bit. It is dissapointing but we had to keep this until I can find another one. The quality is nice. The pics below show shirt on my son and compared to a burts bees size 18 month shirt.