ariel blue dress American Girl Disney Princess Day Dress, Flounder & Accessories for 18-inch Dolls Set the Scene Sometimes Ariel Disney Royal Ball Dress
Description
Its sweatproof and waterproof, Caldwell says

So thank the Lord for technology, iPhones & portrait mode -ha

Fabric = Lace/Chiffon
This plus size sequin formal dress with 3/4 sleeves features a double deep V neckline, long sleeves and a flowy A-line skirt, the shiny sequins stripes decorate the top which gives a chic vibe

Silhouette: Flowy