"I purchased this costume for my 11 year old daughter. When it arrived she tried it on. It fit every where except for in the armpits, sleeve area. Very tight. Her 9 year old cousin tried it on and it was tight on her in the same area. I went online to order a larger size and noticed we had the largest size medium-large for teens. The next size up was for adults and where very sexy. Not something I would let my 11 year old where. Had to return the costume and buy something else."