sorry to break the bad news but u r doomed in this case. Every "service" of that kind in europe requieres and "sms text message" approval. That means in order to track the phone (has to have gps) , to send the text and then the other person has to confirm that she wants to be tracked , very poplular service in my country to track your kids (in this case you program it yourself)
Where can I find this?
I really need it.
Not quite the way he described it but a good app to track family on smartphones is Life360 (https://www.life360.com/)
No one knows what service is he talking about?