Your post is very interesting, due to the similar info I have on my ancestor, Nancy Jane STEPHENSON, b. 3 July 1838, d. 17 March 1913, m. 19 Nov 1857 John William CAST/CASS in Clinton Co, Oh. Nancy is reported to have had a sister, Florence.
Nancy's death certificate shows parents as Joseph STEPHENSON and Mary Ann BANKSTON -- quite a similarity to your Mary Ann BATSON. I have not found any info on Mary Ann except her grave in Clinton Co, near Clarksville, which is in Vernon Twp.
1870 Washington Twp, Clinton Co census shows John CASS and wife Nancy living with their children and Joseph STEPHENSON, age 76 b. Pa. Civil War pension files for John CASS include an affidavit dated 27 July 1888 from Daniel STEPHENSON, age 55, of Cuba, Clinton Co, Oh stating that Daniel has known John CASS for 30 years. That is about the time of John's marriage to Nancy, thus Daniel is probably a Nancy's brother.
What are your sources for William STEPHENSON and Mary Ann BATSON marriage, dates of birth, etc.? What children do you have? Do you know of any connection to my John W. CAST/CASS and Nancy Jane STEPHENSON?