This is my favorite kind of photography.. child candids.
What I notice first off here is that the child has been lightened to the extent that contrast is lost in the facial features. This really pulls a person out of the moment. Be aware that if you do lighten up shadows, to re-add contrast to the black and dark points (eyelashes, important shadow lines, etc.), as it is integral to the realistic and three dimensional aspect of any photo.
Other than that, it's a fantastic moment, and a really cute child.