There is a marriage of a Michael Byrne, solider to Susanna Wall in 1922 Carlowhttps://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_returns/marriages_1922/09206/5330456.pdf
Her Mother was called Mary she died giving birth, her sisters were Bernadette and Patricia, they were sent to the Nuns to raise. Apparently the father Micheal was a Redcoat in the Military.
Assuming Michael was married by 1922, may not have been, there is a Michael Carroll 32 home address Carlow wife Maryhttps://census.militaryarchives.ie/pdf/Gormanstown_2_Eastern_Division_Eastern_Command_Page_22.pdf