Hello Sue, an extract from your Newspaper account says,

John Corkill, the grandfather of the plaintiff, who had been in the navy and afterwards lived in Penzance was the son of John Corkill of the Ards,

I have been reading, ‘ A History of Kirk Maughold ‘
Here are some abbreviated extracts,

Page 295
Corkill, Kerrow ny Ard

William Corkill of Cornaa Purt or Fort, bought the Land in 1717 with his Wife Elizabeth Quay.

NSS Maughold
Old Mau **** 67 Wm Curlett Wm Corkill

William Curlett , formerly of Ballnegorry......

Their Son William to receive half of the Lands. (from his Mother in her Will)
Will of Eizabeth Corkill als Quay – ht tp://www.iomfhs.im/lawsons/LawsonBMD/twill/1738_015.html

She Left to her son Willm Corkill the one half
of their Lands which her husband & she bought
from Willm Curllett formerly of ballnegorrey

Their son William, perished by Sea in 1759

The Will of William Corkill 1765 – leaves the Land to a younger son John (1736 – 1784) who inherited.
ht tp://www.iomfhs.im/lawsons/twill/1765_004.html

Will of their son John Corkill 1784
ht tp://lawsonsiom.freevar.com/wills/1784_075.html

This son John’s (1736 – 1784 - his elder son, also John (b.1771) is thought to be the John Corkill of Ballnegorry referred to in “Manx Worthies”

Certainly the Land passed to the second son Thomas (1780 – 1834)

Not transcribed yet,
Will for - CORKILL, Thomas 1834 Maughold E 2 0106434

Alisons Ancestor - John Corkill of Penzance baptism 1771 IS the son of, John Corkill (1736 – 1784