William Pole-Tylney-Long-Wellesley, 4th Earl of Mornington a very dissipated life and lived for a time in Brussels to avoid his creditors. In his last years he lived on a small pension of ₤10 a week allowed by his cousin Arthur Wellesley, 2nd Duke of Wellington. From 1842 he was styled Viscount Wellesley, and succeeded his father as Earl of Mornington in 1845. He died in lodgings in Thayer Street, Manchester Square, London, on 1 July 1857, from heart disease. The obituary notice three days later in the "Morning Chronicle" claimed that he was "A spendthrift, a profligate, and a gambler in his youth, he became debauched
Richard Wellesley, 1st Marquess Wellesley for many years with Hyacinthe-Gabrielle Roland, an actress at the Palais Royal. She had three sons and two daughters by Wellesley before he married her on 29 November 1794. He moved her to London, where Hyacinthe was generally miserable, as she never learned English and she was scorned by high society: Lady Caroline Lamb was warned by her mother-in-law, Elizabeth Milbanke, a noted judge of what was socially acceptable, that no respectable woman could afford to be seen in Hyacinthe's society. Their children were: Through his eldest daughter Lady Charles Bentinck, Wellesley is a great-great-great grandfather to Queen Elizabeth II.