|Please post the results of an ipconfig /all from your workstation for review.|
What make and model of router? Who installed/configured it?
Your pc should have no effect on his internet connection. This usually happens if the correct cables are not plugged into the correct locations on the router.
Confirm that your pc cable and your husbands pc cable both go into a LAN port. Confirm the cable from the modem goes to the WAN port on the router.
These should be the ONLY connections. No pc to modem connection