William M Jackson/Mariah A. (Mary) Fikes

I am searching for information on this couple from the dates of birth of 1/22/1809, death 1/27/1886 and for Mary,7/18/1811 to 6/7/1894. They lived in Texas and have children buried in Hunt and Erath Counties. They are both buried in Pleasant Grove Cemetery in Pontotoc County Mississippi. They possibly originated from Ireland but that is not confirmed. Any help is welcomed.