Hi Leah,
I recently drilled down and found that i am directly descended from the Upson Georgia Jimmerson clan, some of which migrated to Rusk County, Texas. I found the following:
My gggrandfather is David Edgar (b1889), then John Henry (b1862), then William A. (b1824) and i am trying to connect past the last in line, Thomas (b1800?).
I am having trouble with Thomas and believe that the current birthday of 1800 is likely incorrect. However, his wife Mary Ann Adams has a distinct lineage with good records. Also, perhaps our last name may have been in it's earlier form of Jameson as one might consider the farther you go back in time.
I have recently discovered the ability to look at other 'trees' that Jimmerson relatives had made and made great strides in filling in some blanks.
You can check out mine if you like by searching, 'rjimmerson'.
Hope that helps ~~
Best.