This is one of the cutest photos I've seen in a long time and I would score it as an 11/12
It has almost every element of a merit image. The composition is especially excellent and you snapped the shutter at the perfect moment. The lines of her body, the way she is leaning forward, adds a beautiful flow to the photo. The depth of field is so superb and appropriate . . . and also adds environmental interest without detracting from the center of interest, your granddaughter. I also especially like the BW treatment . . . very appropriate and pleasing.
My only suggestion is that the catchlights in her eyes are not very visible (-1) and could benefit from a little bit of brightening.
Really beautiful work!