Hello David,
Prudence Harris Collins Gibbs was my greatgrandmother. Her son Isaac Collins (with her first husband, James Collins) was my grandfather. I have only followed the Gibbs line forward as far as Morgan Gibbs' marriage to Elizabeth Russell. From this message string I see that I probably didn't get farther because Morgan chose to take the Collins name for a few decades.
I have tried unsuccessfully to follow Prudence's line backward beyond her father and mother, Richard Harris and Sophia Roberts. There is a possibility that Richard was Richard Dobbs Harris the "base born son" of Hannah Harris but I can't be sure. I also haven't been able to determine for sure the date of Richard's death. Do you have any leads that could help?
John Hardy