Donough O'Brien, 2nd Earl of Thomond
Donough O'Brien, 2nd Earl of Thomond, also known as "the fat", was the son of Connor O'Brien, King of Thomond and Annabell Burke. He inherited the earldom from his uncle, Murrough O'Brien, by special remainder.
O'Brien married Helen Butler, daughter of Piers Butler, 8th Earl of Ormonde and Lady Margaret Fitzgerald. He died on 1 April 1553, after being attacked by his brothers at the family seat of Clonroad. O'Brien's brother Donald was named king of Thomond by the Dalgais, but O'Brien's son, Connor, allied himself with the English and regained control of his lands.
Children of Donough O'Brien and Helen Butler:
O'Brien also fathered an illegitimate daughter, Mary, who married Theobald Burke, son of William Burke, 1st Baron Bourke of Castleconnell.
