O'Sullivan grew up in The Lough, Cork. Both of her parents and her grandparents on both sides were singers, though not professionally. She has 3 siblings, including sisters Aoife and Nuala. Nuala represented Cork at the Rose of Tralee in the 1980s. O'Sullivan has a daughter, Christine, an accountant. O'Sullivan lives in Frankfield, Cork. She was nicknamed "Caradiva" by her friends.
Career
O'Sullivan's family noted that her voice began to develop at the age of 12. She attended the Cork School of Music, where O'Sullivan stated that at 17 the head of the school, Jack Murphy, told her parents: "She can go anywhere in the world, she can be anything she wants to be, she can go to the very top." In her 20s, O'Sullivan took a break from singing for 4 years, returning to music after the birth of her daughter. O'Sullivan achieved her first major role in 1996 at the age of 34, as Donna Anna in Don Giovanni with Welsh National Opera. The world renowned Australian soprano Dame Joan Sutherland help O'Sullivan to prepare for the role. In 1997 and 1998, O'Sullivan starred as the Queen of the Night in the Opera North performances of The Magic Flute. The Daily Telegraph praised her "spirit and diamantine accuracy". She appeared on the 2008 anti-domestic violence charity albumSanctuary. She has also performed Così fan tutte, La traviata, Handel's Messiah, and Faust. O'Sullivan's performances have included:
O'Sullivan is a dramatic coloratura soprano. She has been described as a "fearsome coloratura" with "spitfire-like delivery".
Health
Shortly before O'Sullivan was to begin rehearsals in Wales, she was diagnosed with cancer. The stage 2 leg tumour was discovered by her beautician during a waxing session. O'Sullivan has previously dismissed the lump as cellulite. The diagnosis did not affect her performances, as she received initial radiotherapy treatment in Ireland and then in Wales, continuing to work throughout, performing 20 times in 14 weeks. She suffers from insomnia. O'Sullivan has had nodules removed from her vocal cords at the private Blackheath Hospital, London. After the operation, she recuperated at Glenstal Abbey, where she was completely silent for 1 week. In 2018, O'Sullivan was diagnosed with early-onset dementia which led to her retirement from professional singing. Celebratory concerts were organised in her honour in Cork and Dublin.
