<prompt> Qedela umusho olandelayo: Wazalelwa eCobh, eCounty Cork, u-OSullivan wafunda eCobh Community College. Wagcwalisa isitifiketi sakhe sokuphothula izifundo ngo-1987. Umncintiswano wokuqala omkhulu wamazwe omhlaba ka-OSullivan kwaba  <response>: 1990 European Championships eSplit, lapho aqeda khona endaweni ye-11 ku-3000 m. Kodwa-ke, u-OSullivan wathuthuka ngokushesha ngemuva kwalokho, kwathi ngoJanuwari 26 ngonyaka olandelayo, eBoston, wabeka irekhodi elisha lomhlaba elingaphakathi kwe-5000 m ngo-15: 17.28, ethatha imizuzwana engaphezu kwengu-5 kwirekhodi elidala. Ngaleso sikhathi, u-OSullivan owathola umfundaze wezemidlalo wayetadisha i-accountancy e-Villanova University e-US, futhi eMidlalweni Yomhlaba Yabafundi eSheffield ngoJulayi 1991, wanqoba iMedali Yegolide ku-1500 m ngo-4: 2.14, kanye ne- isiliva ku-3000 m ngo-8: 56.55. Ekuqaleni kuka-1992, waqeda endaweni yesikhombisa eMqhudelwaneni Wamazwe Omhlaba Wase-Cross Country. 