We have 2 PC's in the house - both running Eset. Upstairs running Win 7 Home Prem and downstairs (which is connected to the Belkin router) running XP SP3. Our Son has moved back in and after using a Mac Notebook for many years now has a new HP laptop running Win 7. His machine came with Norton A/V, but because the laptop does not have a built in DVD drive, he has not yet loaded the Norton. Should I keep him off the home network? I am concerned that he could bring in a virus and spread it to our 2 PC's.