Sorry Melissa, I had forgotten about that particular thread, but do remember now looking for your JC's parents. Lois and Carol also posted about the family in US records.
Don't let me put you off compiling a combined file of Corkill families! (Although combining the ones from different parishes would be very difficult - you would need to look at a lot of land records and wills.) I can certainly see how the information would be helpful, and also to people like Alison with her John Corkill who lived in Cornwall (recent long thread, which is also unresolved).
Sue