Hi Sue. I know you posted this over 2 yrs. ago, but I'm just going over my old postings on this Board, and I found your question. And, looking at the information on Brian's web site, I see he has a William CORKILL, bap. 1807. This William was a younger brother of my ancestor, John CORKILL, bap. 1798.
Looking at your information, I see your William CORKILL might have been born in 1808, and that is close to 1807, and I'm wondering if he is the same man.
They were sons of John CORKILL and Jane KINREAD, according to researchers. The son, John, had a son, William CORKILL, born ~1826.
It would be nice to find out more about the descendants of John and Esther CORKILL.
Betty (near Lowell, MA, USA)