I already did a review on this costume on Amazon.com.  Interestingly, it isn't showing up now.  Last October, I bought this costume in size 2T/4T and had to sew up the length 4 inches and take about 4 inches in on the sides.  My daughter is almost 4 years old and in the 75th percentile for both height and weight.  She wears a 5T or small girls size 4/5 and this 2T-4T costume was WAY, WAY TOO BIG on her.  I spent hours sewing it so it wouldn't fall off of her shoulders and/or cause her to trip on the length.  Costume was very disappointing and I wonder why the sizing was so off.  The manufacturer did say it ran big but it was ridiculously big and the 2T/4T would probably be big on most 6 or 7 yr olds.  Most parents have better things to do than sew!  Consumers who like to sew for hours will like this costume....everyone else should buy something else!