I recently found Thompson McGuire's estate papers in unbound estate records from Greene County, GA on microfilm 306/24. (Drawer 306, Roll 24.) The downloaded file is 33 pages in PFD format. If you are interested in a copy of the file just let me know.
The file shows that he died instate in Jan. of 1867. There was a disagreement over who should be the administrator of his estate. His widow, Mary, and his eldest son, John L. McGuire, were eventually made administers of said estate. The minor child is NEVER mentioned by name. I suspect that more information will be found in the bound copies of minutes of the Ordinary's office, but that is all have located at this point.
I haven't found a connection between Thompson and members of "my" McGuire's. However, I have reached a point where I copy any McGuire file dating mid 1800's and earlier in Georgia and Alabama. Sometimes I get lucky.