First things first, she's awfully cute! Okay second, everything is quite perfect but you could improve on the legs and arms, because they're rather short but it fits the image. To make your give off a big impact, you could've shaded in parts of the dress and face. Or you could've colored in the eyes with pencil.
And just to give your drawing just a tad of realism, make the hair short of curled, and maybe make the tail look a little animated, because it looks stiff, after it is a tail.

Over all your drawing is cute and appealing.