Complex sentence: McIlroy was born in Holywood, County Down, Northern Ireland, the only child of Gerry and Rosie (née McDonald) McIlroy; he attended St. Patrick's Primary School and then Sullivan Upper School.
Split into simpler sentences: McIlroy was born in Holywood, County Down, Northern Ireland, the only child of Gerry and Rosie (née McDonald) McIlroy. He attended St. Patrick's Primary School and then Sullivan Upper School.