Hello! My Michael McMahon was born in Ballyduneen County Clare Ireland. (probably around 1790) Parish Church of Kilmihil . Kilmihil is approximately 17 miles southwest of Ennis, County Clare, Ireland. That Michael married Honora Reardon.
They had a daughter named Margaret born about 1821, who married a James Purcell. We know that they were in Ellicottville New York for a time. We think Margarets mother Honora Reardon died there while living with her daughter, and we also think her husband James died there as well. I don't know if there is any connection between your Margaret or ours. Like I said earlier, there were PLENTY of Margaret McMahons born in County Clare. But it is worth a shot checking it out. It would be helpful if you knew what Margarets brothers and sisters names were. Our Margarets brothers and sisters name were: John, Simon, Patrick, Thomas, and sister Jane, all born between 1811 and 1830. Good luck in your quest! Jeannie