How do I keep my child from turning off location sharing?

This question has been asked before, but I haven’t seen a good answer. Here’s what I’ve observed:

• On my (adult) iPhone, in settings -> family -> child’s name -> location sharing -> block changes (on), THEN
• On child’s iPhone, in settings -> family -> location sharing -> stop sharing is greyed out,
• On child’s iPhone, in the Find My app there is also no option to stop sharing location with the adult, BUT
• On child’s iPhone, in settings -> privacy & security -> location services -> share my location -> toggle is active.

So it seems that since my child has access to the privacy & security settings on their iPhone they are able to disable all location services and/or just stop their sharing location with me. In other words, I can block some but not all ways of turning off sharing.

Does anyone know how to block this work around on the child’s phone?