I think some kids are just more curious about their bodies than others.
You may want to stress the privacy issue. Just let her know that it is her body so it is okay but it is something she needs to do in private. That's what I told my son when I caught him. I didn't want him to feel shameful about his body and his own natural curiosity. But at the same time I wanted him to understand that if he is going to be doing that it couldn't be out in the open or around people.
There;s certainly a lot of it around and yes some is normal its also good to always be aware ...
I think so. My son never did it, BUT I do know MOSt of my friends kids went though that phase
Unusual, but not abnormal. Try to tell her that "ladies" don't do that. Look a little snotty when you say it. That is what I would do when my little girls did something unacceptable. Being a "lady" sounded very desirable and grownup.