Margaret Costello is the youngest of five children born to Margaret (nee McDermott) and Patrick McGeever from County Roscommon. Margaret was educated at Currasallagh National School and the Vocational School in Ballaghaderreen, Co Roscommon. Margaret worked with the ESB (Electricity Supply Board) in Dublin for six years where she was a member of the ESB’s first ladies’ soccer team and a member of their badminton team. In 1981, Margaret and her husband emigrated to Australia returning to Dublin in 1982, before emigrating to New York the same year to spend a brief period here before returning to Australia. However, due to circumstances, Margaret remained in New York entering the real estate business. Margaret continued to further her education at Queens College and other business institutes in New York. Margaret has worked in real estate management for the past twenty years and is a member of the New York Association of Realty Managers. Margaret has been a member of L.A.O.H. Division 15 Whitestone, NY for twenty-five years, and served as Financial Secretary and Treasurer.

Margaret currently is an officer with the L.A.O.H. Queens County Board and a member of the Irish American Society of Nassau, Suffolk, and Queens. Margaret is the mother of two, Michelle and Matthew, and the grandmother of twin boys, Johnny and Jeremy.