Hi Damian, I'm sorry for not replying to your post sooner. I'm not sure if I understand all of your family connections, but suffice to say, all McSweeneys are related, one way or other, to a common ancestor, no matter how the name is spelled. There is a false claim that we were descended from the O'Neill Kings of Cenel Eoghan -fabricated sometime in the 1400's for political reasons. The fact is, we are of Norse origin and our ancestors ruled the Isle of Man until around the early 11th C, when our eponymous ancestor, Sweyn/Sueno/Suibhne was killed: Suibhne, Son of Cinead [Kenneth], King of the Gal-Gaidhil (foreigne-Gaels) died, AD1034. His grandson Dougal was the castle builder who built Castle Sween, Skipness and Locranza castles. We were one of the original Hebridean and West Highland warrior kindreds and our ancestors' fame and exploits have been largely airbrushed from history. I spent 18 months researching our history! Beware the information on the so-called 'official McSweeney/Sweeney websites, as the authors have a hidden agenda (to stake their own false claims to chieftainship. Best wishes. Julian McSweeney.