I am descended from Mary and her second(?) husband Joseph Cox.I probably have the same information on her that you do - B.Rahway in 1817 and died about 1890.Do you have exact dates?I know that after the death of Joseph, she married James Tway and moved to Alexandria.I also believe that she may have been married before her marriage to Joseph.Do you have any information on a first marriage?
My interest is in finding out about her parents - Jacob Flatt and Hannah Oliver.I have very little information on them.
A Jacob Flatt and Hannah Flatt are listed in the member roll of the Jubilee Souvenir of the 1st Presbyterian Church of Rahway, NJ - published 1891.
Thru findagrave.com I also believe that they are buried in the Rahway Cemetery and that Jacob died in 1819 at the age of 76 yrs.No dates are given for Hannah.
If you have any other information of them, I would greatly appreciate it.