my little girl is 4 and trys to run my life why is that
my 4 year old cousin does the "flashing" thing. i'm not so sure about the mooning though. she's never mooned me. perhaps sitting down with her and asking her why she does that. or trying to explain that flashing, pulling up dresses, tops and mooning are no-no's may help. if she asks why you can tell her why and help to understand why showing the "private" areas is not nice.
Sometimes girls do lift their dress up in public. I know my daughter used to lift her dress up in the stores while shopping every time she saw a little boy. I think it was her playing with the end of her dress and then being excited to see a little boy and the reflex was lifting up the dress.