The line of William is a bit harder to trace as this line has apparently fizzled out quite a bit. There are some descendents of this line still alive in Virginia, but overall, this line was not as prolific as of the sons Thomas and John. I know William must have been a farmer as he received part of his grandfather Robert Flake's acreage plus additonal acreage from his own father. Thus he surely was a fairly substantial farmer.
I do not exactly know the name of William's son. It appears to be Thomas as there is a Thomas Gwaltney mentioned in court record in the early 1700's. However from this line, William does have a grandson named Patrick.
Patrick Gwaltney who was a prominent farmer in the 1790 census and he has to be part of this line since he does not fit into the lines of Thomas or John.
Also from this line comes several generations of Richard Gwaltneys--one of whom had son named William who built a substantial farm still in existence today in Windsor, VA---Indika Farms.