The clearance rack at your local (cheap) formalwear store can be a great source for you portrait wardrobe. The kids spend hours playing with the dresses, but the best part is that they want to have their picture taken after putting on their finishing touches.
When using a wide angle lens, do not get too close to your subject. Perspective distortion can deform their pretty faces. But a wide angle advantage is that it is easier to work above your subject. In this case, getting over the subject allows the big dress to become the background.
This is an ambient window light portrait.