Her father was Brendan MacCarthy, a doctor and a medical inspector in the Local Government Board, and Eleanor McCarthy (née Dexter).
She was remembered by a contemporary as having "beauty and wit threw a vivid light over the front square of Trinity College and over the lectures which were the only function at which, until quite recently, the male and female undergraduates were permitted to forgather.
MacCarthy appears in Beckett's Dream of fair to middling women as "the Alba", and is said to have been the inspiration for the girl in the punt in Krapp's last tape.
By this time she was interested in paediatrics, taking the position of the physician to the children's dispensary at the Royal City of Dublin Hospital.
She left this post in 1954, and was intending on joining the World Health Organization, but failed the obligatory physical examination.
She made a few contributions to the Irish Journal of Medical Science on topics relating to public health problems.
[1] MacCarthy died on 24 May 1959 at the East Ham Memorial Hospital, London, having suffered from throat cancer for a year.