My grandfather was William Emmet Duffy (1900-c.1956) (went by Emmet) of lot 30. My grandmother was Mary Irene Costello (1906-1999) (went by Irene). She was a daughter of Ephraim Costello and Katherine Doherty (or Dougherty).
Irene's uncle, Thomas Alban Costello, married Emmet's cousin, Agnes Quinn (daughter of Sarah Duffy). The Duffy, Quinn, and Costello farms were in close proximity.
My grandmother told me years ago that her Costellos hailed from Kilkenny. The Duffys were from Monaghan.