Ethernet cable problem?

Not sure if this goes in this forum.

My cousin just went somewhere for Christmas but he was using my cable connection, we were both connected via ethernet cables to my linksys router. And they both worked before he left.

Anyhow, he came back today and now connecting via ethernet won't work on his laptop. He can leech off my connection through wifi, but we can't figure out how to reconnect him to the connection through the router. We pretty much arranged our cables in everyway possible in the different slots on the router for ethernet, and also exchanged our cords to see if maybe one of ours wasn't working.

Also unplugged and replugged the cable modem and router. Still, no dice.

What should I do next?

His laptop was probably trying to renew it's IP against the router.. but your computer probably took that IP.. the wireless would work because it picked up a different IP since it's a different network device.

It'll fix itself once the laptop sends a request for a new IP.