Excellent composition and and pose. I think that your use of high key tones here creates an open mood and a sense of emotional purity, which works well in a mother/daughter shot (as I assume this is).
One small suggestion might be to use a reflector to remove the nose shadow on the mother. This shadow could also be softened using the dodge tool in Photoshop, though if you don't have enough facial detail in the shadow, the dodge tool will only take you so far.