Alexander Robert Stewart
Alexander Robert Stewart (12 September 1795 – 25 March 1850) was an Irish landowner and Member of Parliament.
He was the son of Alexander Stewart of Ards by his wife Lady Mary, daughter of Charles Moore, 1st Marquess of Drogheda. His uncle was Robert Stewart, 1st Marquess of Londonderry and he was first cousin to Robert Stewart, 2nd Marquess of Londonderry (a famous Foreign Secretary under the title Viscount Castlereagh) and Charles Vane, 3rd Marquess of Londonderry.
On 28 July 1825 he married Lady Caroline Pratt, daughter of John Jeffreys Pratt, 1st Marquess Camden. Her aunt Lady Frances Pratt was the second wife of the first Marquess of Londonderry and the mother of the third Marquess.