I too would be most intested in any research on this line.

My 3x great-grand father was Robert Quilliam (born about 1800 possibly at Marown) who married Eleanor Quayle of Marown in 1826.
My Robert may have been the son of John Quilliam and Esther Corris and not as I have seen suggested the Robert who was the brother of Captain John.

In effect therefore I am attempting to show that I have no relationship to Captain John and would be grateful for any help in this matter.