I checked out the family of Maj. James Brenton, on Ancestry Family trees. He was born 1740 Va, died 19 Aug 1782 Mercer Co. Ky, Married twice and his children born from 1764 through 1779. No Martha listed. His son James, b 1764 died 1836 in Indana, had no Martha listed either,
1818 is too late for these men I'm afraid.

Howard Boswell