I am currently living in the main residence of a property and have some family staying in a granny flat on our property (looks to be med-long term). I would like to extend the internet to the granny flat and give them their own network and WiFi. My thinking is to run an Ethernet cable from a LAN port on my modem to the granny flat and then plugging this into a separate modem I will locate in the flat through its WAN port. Will this work and will this enable them to have control over their own WiFi as well as have devices plugged directly into that modem/router? Also if there are any better ideas for this setup, I'm keen to hear them.