 However, he broke with Gladstone over Irish Home Rule in 1886 and joined the Liberal Unionists.Grosvenor was the fourth but second surviving son of Richard Grosvenor, 2nd Marquess of Westminster, and Lady Elizabeth Mary, daughter of George Leveson-Gower, 1st Duke of Sutherland.Hugh Grosvenor, 1st Duke of Westminster, was his elder brother.