Question: This British Territorial Army general was succeeded by his son who is estimated to be worth what?

full_context: Document 1: Gerald Grosvenor, 6th Duke of Westminster: Major General Gerald Cavendish Grosvenor, 6th Duke of Westminster, (22 December 1951 – 9 August 2016) was a British landowner, businessman, philanthropist, Territorial Army general and hereditary peer. He was the son of Robert George Grosvenor, 5th Duke of Westminster and Viola Grosvenor. He was Chairman of the property company Grosvenor Group. He is succeeded by his son, Hugh Grosvenor, 7th Duke of Westminster.
Document 2: John Senior: Major (Ret) John Wilson Senior, MBE, TD, mobilised on 27 December 2001, Senior was the first member of the British Territorial Army to be deployed on operational service to Afghanistan (post 11 September 2001). He is also the founder of Heroes Welcome UK, a national scheme to encourage local communities to show their open support to British and other UK-based military personnel.
Document 3: Hugh Grosvenor, 7th Duke of Westminster: Hugh Richard Louis Grosvenor, 7th Duke of Westminster (born 29 January 1991), styled as Earl Grosvenor until August 2016, is a British aristocrat, billionaire, businessman and landowner. He is the third child and only son of Gerald Grosvenor, 6th Duke of Westminster and his wife Natalia Phillips Grosvenor, Duchess of Westminster. He inherited the title of Duke of Westminster on 9 August 2016, on the death of his father. The duke is estimated to be worth US$13 billion, making him the world's richest person aged under 30.
Document 4: Galen Weston: Willard Gordon Galen Weston {'1': ", '2': ", '3': ", '4': "} (born October 29, 1940) is a British-Canadian businessman and philanthropist as well as Executive Chairman of George Weston Limited, a leading food processing and distribution company. Weston and family, with an estimated net worth of $US 8.9 billion, are listed as the second wealthiest in Canada and 147th in the world by Forbes magazine (March 2014).
Document 5: John Paul Getty Jr.: Sir John Paul Getty, KBE (born Eugene Paul Getty; 7 September 1932 – 17 April 2003), was a wealthy American-born British philanthropist and book collector. He was the elder son of Jean Paul Getty Sr. (1892–1976), one of the richest men in the world at the time, and his wife Ann Rork. The Getty family's wealth was the result of the oil business founded by George Franklin Getty. At birth he was given the name Eugene Paul Getty, but in later life he adopted other names, including Paul Getty, John Paul Getty, Jean Paul Getty Jr., and John Paul Getty II. A long-time Anglophile, he became a British citizen in 1997. In 1986, he was awarded an honorary knighthood for services to causes ranging from cricket, to art and to the Conservative Party. His honorary knighthood became substantive when he became a British citizen. In 1998 he changed his name by deed poll when he renounced the first name Eugene and wished to be known as Sir Paul Getty, KBE.
Document 6: David Armstrong-Jones, 2nd Earl of Snowdon: David Albert Charles Armstrong-Jones, 2nd Earl of Snowdon (born 3 November 1961), styled as Viscount Linley until 2017 and known professionally as David Linley, is an English furniture maker and the former chairman of the auction house Christie's UK. The son of Princess Margaret, Countess of Snowdon, and of Antony Armstrong-Jones, 1st Earl of Snowdon, he is a grandson of King George VI and is 18th in line of succession to the British throne, the first in line who is not a descendant of Queen Elizabeth II.
Document 7: Prince George of Cambridge: Prince George of Cambridge (George Alexander Louis; born 22 July 2013) is the elder child and only son of Prince William, Duke of Cambridge, and Catherine, Duchess of Cambridge. He is third in line of succession to the British throne, after his paternal grandfather, and father.
Document 8: Grosvenor House: Grosvenor House was one of the largest private townhouses situated on Park Lane in London. The house was the home of the Grosvenor family (better known as the Dukes of Westminster) for more than a century. Their original London dwelling was on Millbank but, after the family had developed their Mayfair estates, they moved to Park Lane to build a house worthy of their wealth, status and influence in the 19th century.
Document 9: Miles Fitzalan-Howard, 17th Duke of Norfolk: Major General Miles Francis Stapleton Fitzalan-Howard, 17th Duke of Norfolk, (21 July 1915 – 24 June 2002), was a British Army general and peer. He was the eldest son of Bernard Fitzalan-Howard, 3rd Baron Howard of Glossop, and his wife Mona Stapleton, 11th Baroness Beaumont.
Document 10: Alexandra Andresen: Alexandra Gamlemshaug Andresen (born 23 July 1996) is a Norwegian heiress, and as of 2016 , the world's youngest billionaire. Her net worth is estimated at $1.2 billion (£862 million).
Document 11: Charles Armstrong-Jones, Viscount Linley: Charles Patrick Inigo Armstrong-Jones, Viscount Linley (born 1 July 1999) is the only son of David Armstrong-Jones, 2nd Earl of Snowdon, and Serena Armstrong-Jones, Countess of Snowdon. He is a great-grandson of King George VI. He is heir apparent to the Earldom of Snowdon and 19th in line of succession to the British throne, after his father.
Document 12: Alexander Thynn, 7th Marquess of Bath: Alexander George Thynn, 7th Marquess of Bath (born 6 May 1932), styled Viscount Weymouth between 1946 and 1992, is an English politician, artist and author. He was ranked 359th in the "Sunday Times Rich List 2009" with an estimated wealth of £157 million.
Document 13: Robert Grosvenor, 1st Marquess of Westminster: Robert Grosvenor, 1st Marquess of Westminster, {'1': ", '2': ", '3': ", '4': "} (22 March 1767 – 17 February 1845) was the son of the 1st Earl Grosvenor, whom he succeeded in 1802 as 2nd Earl Grosvenor. He was created Marquess of Westminster in 1831. He was an English Member of Parliament (MP) and an ancestor of the modern-day Dukes of Westminster. Grosvenor continued to develop the family's London estates, he rebuilt their country house, Eaton Hall in Cheshire where he also restored the gardens, and built a new London home, Grosvenor House. He maintained and extended the family interests in the acquisition of works of art, and in horse racing and breeding racehorses.
Document 14: Prince Richard, Duke of Gloucester: Prince Richard, Duke of Gloucester, {'1': ", '2': ", '3': ", '4': "} (Richard Alexander Walter George; born 26 August 1944) is the youngest grandchild of King George V and Queen Mary. He practised as an architect until the death of his elder brother placed him in direct line to inherit his father's dukedom of Gloucester, which he inherited, as the second duke, in 1974. He is currently 24th in the line of succession to the British throne. He is also the senior male line descendant of three British monarchs: Victoria, Edward VII and George V .
Document 15: Albert, 12th Prince of Thurn and Taxis: Albert Maria Lamoral Miguel Johannes Gabriel, 12th Prince of Thurn and Taxis (Albert Fürst von Thurn und Taxis; born 24 June 1983), is a German aristocrat, businessman, and race car driver. He has been listed as the world's youngest billionaire many times since his father's death in 1990, first appearing on the list when he was age eight.
ground_truth: US$13 billion