Consistency Check: Abbot Dunan Mac Donachadh born after the death of his mother Gróa Þorsteinsdóttir, of Caithness.Abbot Dunan Mac Donachadh born after the death of his father Duncan, Mórmaer of Caithness.Abbot Dunan Mac Donachadh born after the death of his mother Gróa Þorsteinsdóttir, of Caithness.Hlöðvir Þorfinnsson, earl of Orkney born after the death of his mother Grelod Duncansdatter.
How many of those "death dates" are educated guesses, and how many are Wild Guesses?
This link here Hlodvir Thorfinnsson, Earl of Orkney leads into a timey-wimey mess with Somerled of the Isles in several different places. He's a Duplicate of https://www.geni.com/people/Hlöðvir-Þorfinnsson-earl-of-Orkney/6000... with his name sanded down (and the same is true of the line generally).