Hi! You need to just activate it on the child device. Make sure that you enable GPS on your child's device, by going to settings and tools, phone settings, location, and changing E911 only to GPS or Location On.
Also, you can track your child from your My verizon account 😃 Just login and click on safeguards, and then family locator.
Hope this helped!
LOCATEE is the phone that you wish to activate, it is the phone to be located, and on the ACTIVATION website http://familylocator.vzw.com you will ONLY have an option to activate that phone, so you do not have to worry about deciding which is which.
To login to the familylocator.vzw.com website you will use the LOCATOR login credentials to My Verizon, the LOCATOR is the account you wish to use to locate the other phone. If you do not have a My Verizon login and password you will have the option to do so at http://familylocator.vzw.com it states how to Register if you have not previoulsy:
The activation is laid out step by step at the User guide: http://support.vzw.com/pdf/FamilyLocator_UserGuide.pdf
Please call the individual with the phone you are going to locate, which you explained you don't have, and tell them what to do, i.e. turn the location to ON as described above, and the other 5 steps:
1) have phone on
2) have phone not in use, tell them to leave it alone for 10 minutes while you activate it
3) have phone fully charged, on very weak battery it cannot be activated
4) have phone in coverage area, make sure they have a signal and are not roaming, it should say 3G or EVDO
5) have them leave the phone in site of the sky so the satellites can test locate the phone
Best of luck