suspect Wm Corkil was s/o Wm Corkill + Alice Cannon(m 1739) (had a sib Peter who is mentioned as pledge in Wm's will - also will of Wm senr who d 1781 a year after son Wm (sorry made a type last post)- d 4 sep 1781;douglas;sons thomas,peter;dau isabel;wife alice als cannon exex
I can find a deed of Alice corkill to Peter Corkill but don't as yet have a copy - Alice d 1799 noted as widow of Wm Douglas but doesn't appear to have left a will (maybe the deed was a settlement)