This is a great dress from Kennedy Blue, similar to the J. CREW Heidi silk chiffon dress in Misty Rose. (The Kennedy Blue color is Blush.) No alterations, worn once and cleaned, comfortable for dancing, and affordable! (Retails new for $155 + shipping.)
Sizing: The site suggests the size 4 measurements are: 33" bust 24.5" waist 36.5" hips. I normally wear a street size 2, 32D bust, and the dress fit me loosely but comfortably. I could have had it altered, but it's a pretty forgiving dress and looked fine as is. The self tie belt and loops could be easily removed.
Kennedy Blue website description: The Chloe is a lovely knee length crinkle chiffon V-neck bridesmaid dress. The Chloe features a V-neck neckline, a pleated fitted bodice as well as a figure flattering a-line skirt with a center back zipper and self tie belt at the natural waist.