Charming, chortling little kid here, nicely captured.
This one must be a pleasure to live with.
The only suggestion I would make is in the cropping.
The back of the child's chair is not helping the
composition and by cropping most of it out, right down to the head,
it concentrates the action on that happy smile and the red fruit.
I love how it's not just a baby tasting the food (and obvious shot). The expression is happy, the toung clearly in view, the mess indicating she's had some of the watermelon, along with the bite out of the piece in her hand. I can definately tell this is taste, the textures of the bib and seat help as well.