There are 19 pages on the Mcilhennys at the library of congress. There were four who came to the colonies in 1745, Ezekiel, Robert,they were said to be brothers, and John and Alexander. They came from County Donegal Ire. But there were also McIlhennys i Derry Co. Ire. The family originated in ayre Scotland.I have more info if your interested.