I have just started working on Joseph A. Parker as part of a group of Parkers who were early settlers in Elbert County.
I believe that his Father is a Daniel Parker born 1756. This Daniel is the uncle of the Daniel who gained fame in the Baptist Church as "Two Seed" Daniel. The younger Daniel was also a political leader in Texas. Daniel 1756 had a brother John(father of preacher Daniel) who was a religious leader himself and a victim of the Fort Parker Massacre in Texas. This was the basis of the Movie "The Searchers", and John's grandson was the Comanche chief Quanah.
So I encourage you to work on this connection, it is quite a tribe!