Don't wait too many drinks before you use the flash, as its reflection might give you a headache ;^)
And wise move to not show this to your li'l lady. She might like it so much that you will need to add candy to her water from that moment onward. I have a 5 year old niece ( daughter of my twin sister ) who seems to be addicted to sugar these days and believe me when I tell you that she's already hyper enough without it...
We are lucky with our daughter, as we have kept her largely eating really healthily, as she had allergies early and couldn't eat much. Now, she doesn't really like eating too much sweet stuff :)