Thanks much. I expect I might be related indirectly, but the people I am seeking are a bit earlier. Our Peter and his family left, or most of them did, around 1865. Peter was born possibly 1805-1815. His father was a Thomas, but he would have been older than the Thomas you mention, plus his surname was Faherty. The Clogerty was the wife of Thomas. I expect I am looking for a couple born around 1775-1785, and marrying around 1795-1805.
I do see several records online for the births of Peter and Mary's children, ranging from the late 1830s to the 1850s. Mary was a McDonnell. Two of the records say Ardbear, so I am suspecting that the Peter in Ardbear in Griffiths is likely mine.
It is interesting that Clogerty or Clougherty is such an uncommon name in the states.