I have been working with Carol Dorward of the Washington Historical Society and she has helped me a great deal with Gibson resources in Tazewell, McLean, and Livingston Counties. She did a lot of work on the Washington Presbyterian Church's 175 anniversary celebration was was interested in all the founders, including David and Mercy Gibson and Elizabeth Gibson Reid. I am descended from David's line, through his oldest son, Elisha (Elisha and his two older sisters were a product of a first marriage in OH - - as far as I can determine.) I need to check on your latest list of documents as I think I have not see some of them. I will try to scan the Charlotte bio and get it sent to you. In the meantime, you can contact me directly at tgibson5690 then @ then cox.net. (I try not to put my email address out on these boards all together to try to stay ahead of those spambots).
I have put together all the data I have collected so far on Elisha S. Gibson being a son of David Gibson and it is a part of my public tree here on Ancestry. One of the latest pieces of information on David and Elisha (that CD found) is a letter F.B. Gibson wrote to D.S. Shepard about 1912 or so and was published in the local paper.