using find my phone to "track" kid does it send email or other notice to kid?
Instead of using "find my iphone" use the "find friends" app. It's from Apple and I use it all the time. 

I saw that the OP was using the wrong tool for the job. “Find my phone” does send notices as a feature. Of course if the OP wants to find a lost or stolen phone it’s the right tool and the emails wouldn’t be an issue. 

If the user wants to “track” the other user, however, then “Find Friends” is the correct tool to use