You may be interested in paying a visit to the Thigpen Family GenForum (www.genforum.com/thigpen/
) and search for message number 139. Dennis Hughes posted a reply to another query on 09 July 1999 containing mention of a Nathan H. and Mary Caladonia (ROSS) THIGPEN.
According to his information, this couple had three children: Leak (m?), Mattie, and Fannie Evelyn. One would assume that "Mattie" would be one and the same as Mary Elizabeth, but that would need to be proved through further research. An additional note states that Nathan's household can be found within the 1910 enumeration of Lavaca County. This posting also indicates that Nathan died in Bastrop. So, he may be buried in that vicinity.
Though the poster indicates that this information originates from his "Grandmother Loduska Jane Drury", my research suggests that her source may be Smith's "The Thigpen Tribe", which is known to contain numerous errors. So, the accuracy of any information that you glean from the aforementioned posting should be taken with a large dose of salt.
On a related note, I am collecting information pertaining to all branches of the THIGPEN family that migrated to or through Texas and would welcome any additional information that you may be willing and able to provide regarding your THIGPEN ancestry and the descendants thereof. Feel free to contact me off-list if you are interested.