Please answer the following question: Information:  - Robert Childers Barton (4 March 1881  10 August 1975) was an Irish nationalist, politician and farmer who participated in the negotiations leading up to the signature of the Anglo-Irish Treaty. His father was Charles William Barton and his mother was Agnes Childers. His wife was Rachel Warren of Boston, daughter of Fiske Warren. His double first cousin and close friend was Robert Erskine Childers.  - The Riddle of the Sands: A Record of Secret Service is a 1903 novel by Erskine Childers. The book, which enjoyed immense popularity in the years before World War I, is an early example of the espionage novel and was extremely influential in the genre of spy fiction. It has been made into feature-length films for both cinema and television.  - Erskine Hamilton Childers (11 December 1905  17 November 1974) was a British-born Irish politician who served as the fourth President of Ireland from 25 of June 1973 until his death on 17 November 1974. He was a Teachta Dála (TD) from 1938 until 1973. Childers served as Minister for Posts and Telegraphs (19511954, 19591961, and 19661969), Minister for Lands (19571959), Minister for Transport and Power (19591969), and Minister for Health (19691973). He was appointed Tánaiste in 1969.  - The Irish Civil War (28 June 1922  24 May 1923) was a conflict that followed the Irish War of Independence and accompanied the establishment of the Irish Free State, an entity independent from the United Kingdom but within the British Empire.  - London is the capital and most populous city of England and the United Kingdom, as well as the most populous city proper in the European Union. Standing on the River Thames in the south east of the island of Great Britain, London has been a major settlement for two millennia. It was founded by the Romans, who named it "Londinium". London's ancient core, the City of London, largely retains its medieval boundaries. Since at least the 19th century, "London" has also referred to the metropolis around this core, historically split between Middlesex, Essex, Surrey, Kent, and Hertfordshire, which today largely makes up Greater London, governed by the Mayor of London and the London Assembly.  - Frederick Fiske Warren (2 July 1862  2 February 1938) was a successful paper manufacturer, fine arts denizen, United States tennis champion of 1893, and major supporter of Henry George's single tax system which he helped develop in Harvard, Massachusetts, United States, in the 1930s. Fiske Warren established Georgist single tax colonies and a social experiment in Andorra to disprove Malthus's population theory. He was the son of Samuel Dennis Warren and Susan Cornelia Warren of Beacon Hill, Boston, and the brother to U.S. Attorney Samuel D. Warren and to Edward Perry Warren.   - The Irish Free State (; 6 December 192229 December 1937) was an independent state established in 1922 under the Anglo-Irish Treaty of December 1921. That treaty ended the three-year Irish War of Independence between the forces of the self-proclaimed Irish Republic, the Irish Republican Army (IRA), and British Crown forces.  - Gretchen Osgood Warren (19 March 1868  September 1961), the wife of Fiske Warren, was an actress, singer and poet. The daughter of Dr. Hamilton Osgood and Margaret Cushing Osgood of Beacon Hill, Boston, Massachusetts, her younger sister was Mary Alden Childers, the wife of writer and Irish nationalist Robert Erskine Childers. Her nephew Erskine Hamilton Childers served as the fourth President of Ireland from 1973-74.  - The British Broadcasting Corporation (BBC) is a British public service broadcaster. It is headquartered at Broadcasting House in London, is the world's oldest national broadcasting organisation, and is the largest broadcaster in the world by number of employees, with over 20,950 staff in total, of whom 16,672 are in public sector broadcasting; including part-time, flexible as well as fixed contract staff, the total number is 35,402.  - Robert Erskine Childers DSC (25 June 1870  24 November 1922), universally known as Erskine Childers, was the author of the influential novel "The Riddle of the Sands" and an Irish nationalist who smuggled guns to Ireland in his sailing yacht "Asgard". He was executed by the authorities of the nascent Irish Free State during the Irish Civil War. He was the son of British Orientalist scholar Robert Caesar Childers; the cousin of Hugh Childers and Robert Barton; and the father of the fourth President of Ireland, Erskine Hamilton Childers.  - The President of Ireland is the head of state of Ireland and the Supreme Commander of the Irish Defence Forces.   - Robert Caesar Childers (1838  25 July 1876) was a British Orientalist scholar, compiler of the first Pli-English dictionary. Childers was the husband of Anna Barton of Ireland. He was the father of Irish nationalist Robert Erskine Childers and grandfather to the fourth President of Ireland, Erskine Hamilton Childers.  - A TD (plural TDanna in Irish; full Irish form Teachta Dála , , plural "Teachtaí Dála") is a member of Dáil Éireann, the lower house of the Oireachtas (the Irish Parliament). It is the equivalent of terms such as "Member of Parliament" (MP) or "Member of Congress" used in other states. The official translation of the term is "Deputy to the Dáil", although a more literal translation is "Assembly Delegate".  - Broadcasting House is the headquarters of the BBC, in Portland Place and Langham Place, London. The first radio broadcast was made on 15 March 1932, and the building was officially opened two months later, on 15 May. The main building is in Art Deco style, with a facing of Portland stone over a steel frame. It is a Grade II* listed building and includes the BBC Radio Theatre, where music and speech programmes are recorded in front of a studio audience, and lobby that was used as a location for filming the 1998 BBC television series "In the Red".  - The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a sovereign country in western Europe. Lying off the north-western coast of the European mainland, it includes the island of Great Britain (the name of which is also loosely applied to the whole country), the north-eastern part of the island of Ireland, and many smaller islands. Northern Ireland is the only part of the UK that shares a land border with another sovereign statethe Republic of Ireland. Apart from this land border, the UK is surrounded by the Atlantic Ocean, with the North Sea to its east, the English Channel to its south and the Celtic Sea to its south-south-west, giving it the 12th-longest coastline in the world. The Irish Sea lies between Great Britain and Ireland. With an area of , the UK is the 78th-largest sovereign state in the world and the 11th-largest in Europe. It is also the 21st-most populous country, with an estimated 65.1 million inhabitants. Together, this makes it the fourth most densely populated country in the European Union.  - Erskine Barton Childers ( 11 March 1929 -- 25 August 1996 ) was a writer , BBC correspondent and United Nations senior civil servant . He was the eldest son of Erskine Hamilton Childers ( Ireland 's fourth President ) and Ruth Ellen Dow Childers . His grandparents Mary Alden Childers and Robert Erskine Childers and the latter 's double first cousin Robert Barton were all Irish nationalists involved heavily with the negotiation of Irish independence ; which ultimately led to his grandfather 's execution during the Irish Civil War . His great aunt was Gretchen Osgood Warren .  - Hugh Culling Eardley Childers (25 June 1827  29 January 1896) was a British-Australian Liberal statesman of the nineteenth century. He is perhaps best known for his reform efforts at the Admiralty and the War Office. Later in his career, as Chancellor of the Exchequer, his attempt to correct a budget shortfall led to the fall of the Liberal government led by William Ewart Gladstone.  - The British Empire comprised the dominions, colonies, protectorates, mandates and other territories ruled or administered by the United Kingdom and its predecessor states. It originated with the overseas possessions and trading posts established by England between the late 16th and early 18th centuries. At its height, it was the largest empire in history and, for over a century, was the foremost global power. By 1913, the British Empire held sway over 412 million people, % of the world population at the time, and by 1920, it covered , % of the Earth's total land area. As a result, its political, legal, linguistic and cultural legacy is widespread. At the peak of its power, the phrase "the empire on which the sun never sets" was often used to describe the British Empire, because its expanse around the globe meant that the sun was always shining on at least one of its territories.  - The Anglo-Irish Treaty, commonly known as The Treaty and officially the Articles of Agreement for a Treaty Between Great Britain and Ireland, was an agreement between the government of the United Kingdom of Great Britain and Ireland and representatives of the Irish Republic that concluded the Irish War of Independence. It provided for the establishment of the Irish Free State within a year as a self-governing dominion within the 'community of nations known as the British Empire', a status 'the same as that of the Dominion of Canada'. It also provided Northern Ireland, which had been created by the Government of Ireland Act 1920, an option to opt out of the Irish Free State, which it exercised.  - The Minister for Posts and Telegraphs (sometimes called the P&T in English or PT in Irish, and later stylised P+T) was a senior post in the government of the Irish Free State and Ireland from 1924 to 1984, when the post and the department were abolished.  - The Tánaiste is the deputy prime minister of the Republic of Ireland and the second-most senior officer in the Government of Ireland. The Tánaiste is appointed by the President of Ireland on the advice of the Taoiseach. The current office holder is Frances Fitzgerald, TD, who was appointed on 6 May 2016.  - The Irish War of Independence or Anglo-Irish War or the Tan War was a guerrilla war fought from 1919 to 1921 between the Irish Republican Army (IRA, the army of the Irish Republic) and the British security forces in Ireland. It was an escalation of the Irish revolutionary period into armed conflict.    After reading the paragraphs above, we are interested in knowing the entity with which 'erskine barton childers' exhibits the relationship of 'occupation'. Find the answer from the choices below.  Choices: - actress  - army  - author  - book  - broadcaster  - canada  - chancellor  - deputy  - farmer  - guerrilla  - head of state  - manufacturer  - mayor  - member  - minister  - officer  - orientalist  - poet  - politician  - president  - public service  - radio  - revolutionary  - singer  - sovereign  - spy  - statesman  - television  - translation  - united kingdom  - writer
Answer:
author