From FibreMood:
Willa is a fluid, minimalist wrap dress that falls just under the knee with raglan sleeves and a high, round neckline. This dress offers limitless possibilities: you can take it in, turning it into a mini dress, or lengthen it into a mid-calf or floor length dress. The sleeve length can also be altered, and the fashioned waist tie can be made in two lengths. The shorter version only knots at the back and requires less fabric. The longer version wraps around the back to the front, where it can be tied in a bow. This version requires a little more fabric.
Fabric advice
The Willa dress should be made in a medium-weight, slightly stretchy fabric with a fluid drape. Knitted and woven fabrics both work for this purpose.