Richie House Girls' Sequined Party Dress Size 2-10Y RH2264 100%polyester Lining:100%cotton A size 4 is for the average 3-4 year old girl, a size 5 is for the average 4-5 year old girl, a size 9 is for the average 8-9 year old,etc Sequined embroidery and a bright hue add some girly flair, and light materials with glitterling give it effortless twirlability. A zipper up the back makes dressing little ones easy-breezy Little ladies will be the belle of the ball when they don this darling dress.