Remona from The Stitching Scientist shows how to make an easy knit sundress for a little girl. The bodice is simply a tube of knit fabric, with ribbons for straps and a skirt gathered to the bottom. You can make it any length from tunic top to maxi dress. The textured knit she used for the one in her post is super cute! Go to The Stitching Scientist to get her tutorial.
[photo from The Stitching Scientist]