Hi David,
Thanks for the update, and bad luck that the certs only had IOM as his birthplace. My IOM ancestor put her birth parish as well as IOM on 3 or 4 of her seven children's birth certs. I "viewed" them all in the days when you could do that, and didn't have to buy the copies.
- And even if you had that information it would still be difficult to separate the two Maughold William Corkills both b.1816. Were the names Patrick, Catherine, Thomas, or Elinor used for any of John's children? Or one of the mothers' maiden surnames used as a second name?
Sue