Saoirse-Monica Jackson Erin Actor Louisa Harland Orla Actor Kathy Kiera Clarke Aunt Sarah Actor Tara Lynne O'Neill Ma Mary Actor Siobhan McSweeney Sister Michael Actor Tommy Tiernan Da Gerry Actor Ian McElhinney Granda Joe Actor Foy Vance Singer Actor Jamie Beamish Ciaran Actor Philippa Dunne Geraldine Devlin Actor David Ireland Sean Devlin Actor Amelia Crowley Deirdre Mallon Actor Alex Gaumond Rob Actor Justine Mitchell Adult Janette Actor Tobias Beer Richard the Surgeon Actor Shauna Higgins Wee Ma Mary Actor Dearbháile McKinney Wee Aunt Sarah Actor Jessica Reynolds Wee Deirdre Actor Therese Cahill Sister Benedict Actor Lisa McGee Writer, Executive Producer Michael Lennox Director Caroline Leddy Executive Producer Noel Hogan Music Liz Lewin Executive Producer Jimmy Mulville Executive Producer