He never married and was succeeded by his younger brother, the fifth Earl. His son, the sixth Earl, was a major-general in the army and served as a Deputy Speaker of the House of Lords from 1976 to 1989. The titles are held by the latter's only son, the seventh Earl, who succeeded in 1999. He is one of the ninety elected hereditary peers that remain in the House of Lords after the passing of the House of Lords Act 1999, and sits on the Conservative benches. Lord Cathcart lost his seat in 1999 but was able to return in 2007 in a by-election caused by the death of Lord Mowbray. He is also chief of Clan Cathcart. Several other members of the family may also be mentioned. The Hon. Sir George Cathcart, fourth son of the first Earl, was a general in the army. The Hon. Charles Cathcart, younger son of the ninth Lord, was a colonel in the British Army and represented Clackmannanshire in the House of Commons. The Hon. Louisa Cathcart, daughter of the ninth Lord, married David Murray, 7th Viscount of Stormont. In 1793, on the death of her and Lord Stormont's uncle William Murray, 1st Earl of Mansfield and Mansfield, Louisa inherited (under a special remainder in the letters patent) the earldom of Mansfield created in 1776, and became the second Countess of Mansfield, while her husband inherited the earldom of Mansfield created in 1792, and became the second Earl of Mansfield (see the Earl of Mansfield and Mansfield for later history of these titles). The family seat is Gateley Hall, near Fakenham, Norfolk. The heir apparent is the present holder's son Alan George Cathcart, Lord Greenock (born 1986)