I love this dress. It is so girly and frilly. My daughter is almost 6 years old and normally wears a size 6 or 7. I read other reviews complaining that this dress was small so I ordered a M instead of I which I would normally get my daughter. It is way too big. I don't think this dress runs small at all. I am ordering another one in I and will save the M for later. I would guess the medium is around a size 8 or 9.
We purchased the rose and the lavender for our spring recital. The dresses were beautiful! The little dancers loved them because they are so soft. The chiffon skirts flowed with the movement. I highly recommend this dress to anyone needing quality costuming for little dancers!