When I use the find my iPhone app it does not send an email. Even when I go to
www.icloud.com and use the find my iPhone feature there, it still does not send an email. The only time it sends an email is when I hit the play sound button so I can find my daughters iPhone lost in the house somewhere, then it sends an email, but simply using the app and looking on a map to see where the device is, its never sent an email.
The other day my wife somehow ran out of gas while driving (yeah I know lol), was not sure exactly where she was. I used the find my iPhone app and got turn by turn directions to where she was at, which was pretty slick. And it never sent an email. She is on iOS 6 and I am on iOS 8.
It is a nice little feature.
If it were me, I would set up an iCloud account strictly for using find my iPhone and do not give out the password. This way it cannot be disabled on the device. The only way it would be disabled is if she turns the phone off. I would tell my kid, your under my roof and I am paying for your phone, these are the rules.