Tabitha Lawrence (Vaughan) - marriage and children Abraham Lawrence

I am trying to "sort-out" the marriages of Abraham Lawrence. I have found three wives. I cannot find records of all three. I would like to determine the children of Abraham (who belonged to which wife.) Stephen is supposedly the child of Tabitha Vaughan, born in 1777; if they did not marry until 1823,,she would have 58 when she married Abraham and cannot be the mother of Stephen as recorded in some genealogies.
Have I befuddled myself, looking at something wrong?? HELP