Mary Abercrombie Bradberry is probably the daughter of Colville Abercrombie Jr. (4 Oct 1793-26 Aug 1838) and wife, Sarah Mahaffey (4 Jan 1799-1863) who moved from Laurens Co. SC to Clayton Co. (now Henry Co.) GA.
In Colville Abercrombie Sr.s'(1762-1847) estate file Box 110, Package 8, Laurens Co. SC, there is a sale bill dated 20 Oct 1853 and it says "the children of Colville Abercrombie, dec'd is entitled to one share of $233.56. He left 7 children and each individual share is $33.36."On another page dated 1854 payment in that amount is made to Abercrombie's named John, Elihu, Colville, Rachel and a name that looks like Amanda, but I believe it should read Lavinda.I figure the 5 named are Colville Srs.' grandchildren and the children of Colville Jr. who had died before Sr. The 2 children who were not named were probably not of legal age to receive their share in 1854 and one was most likely your Mary.
Clayton Co. GA Will Book A contains 2 wills that are helpful. Sisters Lavinda and Rachel Abercrombie did not marry.Lavinda left all her estate to sister Rachel Abercrombie in her will written 9 Jan 1868 and probated 3 Aug 1870. Then Rachel Abercrombie in her will left all to her sister, Mary Bradberry, 19 May 1884.I should add that I have a death date of 30 Jan 1883 for Rachel Abercrombie from a Clayton Co. GA cemetery book. So, I'm uncertain if the 1884 date of her will is correct. Perhaps that is a probate date or there is a transcription error in the will or cemetery book listing.
I hope this will help you and if my logic is incorrect I hope someone will respond to assist.Linda