So I'm staying in my grandparents apartment with my family, and my 12 year old cousin just sits here and plays Fortnite. He also uses and Ethernet cable and turns off the WiFi to hog all of the bandwidth. I need a way to stop his Ethernet cord from working while also making it hard to notice why it stopped working. However, I have to be able to fix it so I don't have to pay for a new one.
The simpler the better, Thanks.