>>106369708
Happens
>>106370636
I'm going to give you real advice.
>Get a router that can support vlans(High chance you already have one if you have that setup)
>Buy a managed switch get the cheapest you can find
>create a vlan
>give it the same credentials as your family used network
>put firewall rules that prevent them from touching the router itself or anything on your current network.
>Use the network with your desired blocks anyway you see fit
Some routers make vlans simple if you're using something like openwrt you'll need to read about appropriate setup, but it's really simple after the first time.