She is well known for performing old Irish songs in her native Irish and in English. Her albums include Ailleog and Doagh, on which she covered such songs as "Ar Éirinn Ní Neosfainn Cé Hí" and "Song Foreign Ireland". In 2007, McCool was married and worked as a national school teacher in Dunshaughlin in County Meath.
McCool took part in the Eurosong competition on The Late Late Show on February 24, where she performed "Mistaken", written by Edele Lynch.
She finished in fifth place.