Hi Menapi,
Your Great Great Grandfather Patrick Corcoran married Mary Barry. They had a son John Corcoran.
John married Kate Morrissey.
They had 13 children, of which 10 were living: see 1911 Census for 4 Hughes Lot East, Cashel. Also see 1901 Census.
One of their children William joined the Leinster Regiment at the outbreak of WW1. He served in France and Flanders, and was killed on 6 November 1917.
Another of their children Patrick went to USA. He worked as a shipping clerk in Boston, then enlisted with the U.S. Army at Boston. He served with them in France, and was honourably discharged from the U.S. Army in April 1919.
Do you know anything about a story behind the reasons William joined the British Army, and Patrick went to USA?