Mary O'Brien Peerage person ID=483121 (b. 1620) Parents Una O'Brien Connor O'Brien, 3rd Earl of Thomond Children Máire Rua O'Brien Siblings Daniel O'Brien, 1st Viscount Clare Teige O'Brien Margaret O'Brien Lady Honor O'Brien Donogh O'Brien, 4th Earl of Thomond Honora O'Brien Partners Turlough Roe MacMahon