I found another solid clue in Massachusetts to possibly help narrow down 2x great grandfather Edward Comerford parents. He very likely had a brother named John.born about 1819.
Can you try and find both and Edward and John in those date ranges, maybe between 1810 and 1825 with the same parents? possibly at ST JOHN's
John Comerford-At the National Soldiers' Home, Togus, Me., Jan. 18, 1909 John Comerford 89 yrs. 8 mos. Late member of Co, A, old 9th Mass. Volunteers. Funeral from the residence of his niece, Mrs. Margaret Ford (nee Comerford I, 320 Columbia St. Cambridge, Friday, 22, at 830.
The funeral was held from the residence of his niece, Mrs. William A. Ford, 320 Columbia street,
My analysis of the clues - I think fairly conclusive that John and Edward were brothers.
1) - Margt Comerford mentioned above born Sep 1864 in Kilkenny, Parents Edward and Alice Arkwright
2) - Alice (Arkwright) Comerford 1889 funeral was at Margaret Ellen Comerford house in Cambridge, Mass, USA
3) - Margaret Ellen Comerford 1898 married to William Allen Ford - parents Edward and Alice Arkwright - neighboring city Somerville, MAss USA
4) - John Comerford funeral at house of his niece Mrs William A Ford in one newspaper, Mrs Margaret Ford (nee Comerford) in another Cambridge Mass, USA. He also was in the same house in the 1900 census, but listed as lodger.