So far all I have found Thomas wise where a child fits to be Mary Francis Thomas is this. 1870 Tippah HH 5, William A Thomas 29 @ (1841) b NC, M. A. Thomas 27 @ (1843),b MS, JW Thomas (m) age 8 (b @ 1862) MS, M F age 4 (Mary Francis?) (f) age 4 (b @ 1866) b MS, WA Thomas (f)age 2 b MS @ (1868) and a Thomas Westley age 19 b @ (1851) MS.
The daughter M F's age4 would be about the right age to be Mary Francis.
Do you know where Amanda and her two sisters, Nancy and Franky were living before 1880?