This is exactly why I force my kids to always create accounts as 30-years old (by specifying a birth data in the 90s), to avoid as much State interference as possible. Did you know that if your child has a "kid" account you cannot follow him on google maps? We had to make one for "adults" in order to be able to do so.
How about OwnTracks?
Zood Location is pretty good. Open source, location data is end-to-end encrypted (encrypted to the keys of the people you are sharing with before it leaves your device).