Pat, Would you have further information on McCormick please ?
In the "Bellegrove" Adair lineage (which may or may not be correct)it gives the story of Thomas Fitzgerald, 6th Earl of Desmond m. dau. of William McCormic and they had son Maurice.The it notes that Maurice had issue: 1.Robert, ancestor of the Adairs and 2.Maurice, ancestor of the Fitzgeralds of Brogil/Brogyl. (Perhaps Earl of Cork lineage ?)
Then it stated that Robert returned to Ireland with the hope of regaining his family title and estates (I took it to be those of his grandfather) and killed Gerald, the White Knight (stated in "Bellegrove" lineage to be the 2nd son of Gerald, the then Earl of Desmond).
Would be interested to see if we could attack this puzzle from the McCormick side.
Think the index of the Calendar of State Papers - Ireland may have been c.late 1500s so will have to check as we are talking of Adair leaving Ireland c.1420 and his grandson returning to Ireland perhaps 1480s ? This would be about the time that the Adair married Miss Stewart as I had that her father was killed in the battle in England in 1513.