Thank you Frances.

Then most likely the son of Patrick Corkill (also a son of William Corkill & Margaret Corlet) and his wife Jane Cubon.

I noticed today that there was a John Corkill (too a son of William Corkill & Margaret Corlet) who married an Ann Cubon. Ann died in 1735 (1735-2 A 41 CORKILL Ann CUBBON bur 14 Feb 1735;husb John;ch Jony(a dumb girl); Witt Robert Curghey x, William Cubon x; inv inc 2 cows, 13 sheep) and her husband John Corkill died in 1738 (1738-2 A 75 CORKILL John d 10? Nov 1738;ch Joney(dumb girl - a cow in lieu of mo's goods - also his part of house, exex), Ann; Sibs Wm + Dorothy(w/o Robt Curghy) to be supvs of Joney;wife alive;1739: supvs threatened with prison unless they give bond of £3 to perfect the inv).

The mention in John's 1738 will of William and Dorothy being supervisors to dumb girl Joney may suggest that the William I am searching for was alive at least until 1738.

Dorothy Corkill was also a child of William Corkill & Margaret Corlet.

The wife "alive" in John's will appears to be his second wife Jane Gellin (m. Braddan 4 Jun 1737). They appear to have had the other child Ann listed in John's 1738 will (b. 17 Jul 1737 Braddan).

What do you think about the attachment to John's will that says "spvs threatened with prison unless they give bond of £3 to perfect the inv."

I will keep floundering about, and trying to tighten the knot around that allusive William Corkill (child of William Corkill & Margaret Corlet)