Your grandmother and my great-grandfather, James Martin Pierce would have been brother and sister. He, too, married a Karr. In Marion County Alabama at the time I suppose there were not a lot of families. I also have the picture of Matthew and Sarah if you would like it. If you are a member of ancestry you can download it through the Moss Family Tree. Do you know who John Thomas' parents were? In my research I have it as Isaac and Rebecca Pierce because of a census record I found with a John of the right age in Alabama. However, I am not sure it is right.
Heather Pierce Smith