In PRTG, to manually setup dependencies, go to Devices -> Dependencies in PRTG:
The PRTG Dependencies system requires manual assignment of dependencies to your devices. This can be a painstakingly slow process.
If you’d like to automate this process, UVexplorer can assign dependencies automatically to current PRTG groups.
To automatically create dependencies for PRTG groups, right click the map and go to Export – > Export to PRTG…: