John Cahill B 17 D 1812 Need Parentage M Eleanor Butts

Looking for the parentage and burial place of John Cahill.
He married Eleanor Butts in 1795 in Culpepper, VA
His birth year is unknown but he died 10-31-1812.
He was enlisted in the Mounted Volunteers in the War of 1812, but only for a month.
I have his 9 children, etc. But have no other info on him. He and parents "may" have been from Ireland. (so said my great-grandfather).