Mary FitzMaurice, 4th Countess of Orkney was a Scottish peer, the only surviving child of Murrough O'Brien, 1st Marquess of Thomond and Mary O'Brien, 3rd Countess of Orkney.

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Mary FitzMaurice, 4th Countess of Orkney was a Scottish peer, the only surviving child of Murrough O'Brien, 1st Marquess of Thomond and Mary O'Brien, 3rd Countess of Orkney.

From Wikipedia (CC BY-SA 4.0).