Question: The Chief Mouser to the Cabinet Office is the title of the official resident cat, of the Prime Minister of the United Kingdom, which tabby cat, with this title, is owned by the former Chancellor of the Exchequer of the United Kingdom George Osborne and his family?

Context paragraphs:
Freya (cat): Freya (born c. April 2009) is a tabby cat owned by the former Chancellor of the Exchequer of the United Kingdom George Osborne and his family.

Larry (cat): Larry is the 10 Downing Street cat and is Chief Mouser to the Cabinet Office.  Larry is a brown and white tabby, believed to have been born in January 2007.  By July 2016, when Theresa May became Prime Minister, Larry had developed a reputation of being "violent" in his interactions with other local mousers, namely the Foreign Office's much younger cat Palmerston.

Chief Mouser to the Cabinet Office: The Chief Mouser to the Cabinet Office is the title of the official resident cat of the Prime Minister of the United Kingdom at 10 Downing Street.  Only four cats, Humphrey, Sybil, Larry and Freya have been given the title officially; other cats were given this title affectionately, usually by the British press.  There has been a resident Treasury or Downing Street cat employed as a mouser and pet since the reign of Henry VIII, when Cardinal Wolsey placed his cat by his side while acting in his judicial capacity as Lord Chancellor, an office he assumed in 1515.

David Howell, Baron Howell of Guildford: David Arthur Russell Howell, Baron Howell of Guildford PC (born 18 January 1936), is a British Conservative politician, journalist, and economic consultant.  Having been successively Secretary of State for Energy and then for Transport under Margaret Thatcher, Howell has more recently been a Minister of State in the Foreign Office from the election in 2010 until the reshuffle of 2012.  He has served as Chair of the House of Lords International Relations Committee since May 2016.  Along with William Hague, Sir George Young and Kenneth Clarke, he is one of the few Cabinet ministers from the 1979–97 governments who still holds high office in the party, being its deputy leader in the House of Lords until 2010.  His daughter, Frances, is married to the former Chancellor of the Exchequer, George Osborne.

Humphrey (cat): Humphrey (c. 1988 – March 2006) was a cat employed as the Chief Mouser to the Cabinet Office at 10 Downing Street, the official residence of the Prime Minister of the United Kingdom, from October 1989 to 13 November 1997.

Peta (cat): Manninagh KateDhu, commonly known as Peta, was the Chief Mouser to the Cabinet Office of the United Kingdom government between 1964 and sometime between 1969 and 1976, and was the first female cat in that role.  She became the replacement to Peter III, who had died at the age of 16 in 1964.  After Peter III's death, the Lieutenant Governor of the Isle of Man, Sir Ronald Garvey, suggested that a Manx cat be his replacement, and sent Peta to the Cabinet.  She was noted to be lazy and loud, and by 1969, some civil servants tried to remove her from Cabinet, but this did not happen, because of the suspected bad publicity that this action would incur.  She was not heard of again, until a reply to a member of the public in 1976 revealed that she had retired to the home of a civil servant.  Her successor was Wilberforce, who became the next Chief Mouser in the 1970s.

Sir Peter Osborne, 17th Baronet: Sir Peter George Osborne, 17th Baronet (born 29 June 1943) is a British businessman, who co-founded the interior design firm Osborne & Little.  He is the father of George Osborne, the Conservative politician and former Chancellor of the Exchequer.

Gladstone (cat): Gladstone is the resident Chief Mouser of HM Treasury at Whitehall, London.  He is a domestic short-haired cat, who, at eighteen months old, assumed the position of Chief Mouser in late June 2016.  Gladstone's political namesake is former Chancellor and Prime Minister William Ewart Gladstone who served for four separate periods, more than any other Prime Minister.  The hope is Gladstone will control mice at the Treasury's 1 Horse Guards Road building.

Secretary to the Treasury: In the United Kingdom, there are several Secretaries to the Treasury, who are Treasury ministers nominally acting as secretaries to HM Treasury.  The origins of the office are unclear, although it probably originated during Lord Burghley's tenure as Lord Treasurer in the 16th century.  The number of secretaries was expanded to two by 1714 at the latest.  The Treasury ministers together discharge all the former functions of the Lord Treasurer, which are nowadays nominally vested in the Lords Commissioners of the Treasury.  Of the Commissioners, only the Second Lord of the Treasury, who is also the Chancellor of the Exchequer, is a Treasury minister (the others are the Prime Minister and the Government Whips).  The Chancellor is the senior Treasury minister, followed by the Chief Secretary to the Treasury, who also attends Cabinet and has particular responsibilities for public expenditure.  In order of seniority, the junior Treasury ministers are: the Financial Secretary to the Treasury; the Economic Secretary to the Treasury; the Exchequer Secretary to the Treasury; and the Commercial Secretary to the Treasury (Office currently not in use).  One of the present-day secretaries, the Parliamentary Secretary to the Treasury, formerly known as the 'Patronage Secretary', is not a Treasury minister but the Government Chief Whip in the House of Commons.  The office can be seen as a sinecure, allowing the Chief Whip to draw a government salary, attend Cabinet, and use a Downing Street residence.

Palmerston (cat): Palmerston is the resident Chief Mouser of the Foreign & Commonwealth Office (FCO) at Whitehall, London.  He is a two-year-old, black and white, bicolour cat, who began his role and the position of Chief Mouser on 13 April 2016.  Previously, he was from Battersea Dogs & Cats Home and is named after the former Foreign Secretary and Prime Minister Lord Palmerston.  He is employed at the King Charles Street building.

Supporting paragraphs: Chief Mouser to the Cabinet Office Freya (cat)
Answer: Freya