[2][3][4] She was educated at Laurel Hill Convent in Limerick,[5] before earning a BA at University College Dublin and emigrating to England.

She was made a life peer as Baroness O'Cathain, of The Barbican in the City of London, on 21 June 1991[7] and sat in the House of Lords on the Conservative benches.

She was known for her socially conservative views, in particular her efforts to retain the ban on same-sex couples from adopting, and had taken on a leadership role against gay rights after the death of Lady Young.

[8] In 2004, Lady O'Cathain denied that her decision to step down from the board of British Airways was connected with a threatened boycott of the airline by gay rights group Stonewall.

[10][11] In 2014, Baroness O’Cathain was selected to chair the House of Lords inquiry into civil use of remotely piloted aircraft systems (RPAS), devices commonly referred to as drones.