Hello Sue, I have been following the Corkill;s from Maughold.
I have searched through my ' Ballajora ' Corkill's and found.

These 2 Ballajora Corkill burials - could be - the parents of Robert Corkill - his Baptism, 14 Sep 1806.

Corkill, B'jorey 15 January 1821 William Corkill's wife (died of Smallpox).- Elinor Corkill alias Christian.

Corkill, Wm B'Jorrey 72 yrs 8 October 1836..

This could fit in as the Son of, William Corkill and Margaret Callow.

Name William Corkil.
father: Wm Corkil.
mother: Margt Calow.
Christening Date16 Jun 1765.
Christening Place Maughold,Isle of Man.

The only other way to trace back further (if there are no Wills for them) is to search the Land Records.

Averil