 McCool grew up as a member of the choir at St. Mary's church in Gweedore, singing alongside Enya, Aoife Ní Fhearraigh, Moya Brennan and other members of Clannad who are also members.Her music teacher at Pobalscoil Ghaoth Dobhair was Baba Brennan, the mother of Clannad and Enya.McCool took part in the Eurosong competition on "The Late Late Show" on 24 February 2012, where she performed "Mistaken", written by Edele Lynch.