Henry and Rebecca were in Kinnitty, Birr, in what was then King's County, at 1913 and 1916, having a Henry Hugh McKinley born on 20/6/1913 and a Martha Irene McKinley born on 12/4/1916.Another 3 possible births in the Birr area after this too, but I won't add names here as within 100 years.
Henry and Rebecca's 1919 born daughter married a soldier in County Meath in 1941. Witnesses look to have been her mother and her 1922 born brother.
.......also found out that rebecca moved to England london with one of her daughters she died aged 75 years and is buried in Tooting.
She married Joseph Reid, who was a soldier in the Irish Guards.https://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_returns/marriages_1941/08830/5193114.pdf