All you would likely find are some sundews (rotundifolia, perhaps brevifolia or capilaris) and Utricularia. There are still plenty of sphagnum bogs in Virginia, but most of them have been overgrown with trees due to fire supression. So there might be enough light for Sphagnum, but not enough light to sustain many CP's. Unless your gandparents have kept these areas clear of trees, this is likely the case on their land as well.
It's always exciting to see what you can find though, in any case. Let us know what it looks like when you go to see! Post pics if you can, as I'm sure we would all love to see what's there.
If by some wild string of luck you find a Sarracenia purpurea or flava on their land, that is VERY RARE in virginia and you shouldn't collect those. Phil Sheridan at Meadowview Biological Research Station would be very interested if you found either of those (for preservation purposes), but again, the chances of that are VERY slim. There are other rare bog plants that you have a slim chance of seeing, but should keep an eye out for and which should be preserved if possible, including some bog orchids and D. intermedia, among others.