Question: Flying ace Peter Townsend was romantically connected to what British princess directly following his service to Queen Elizabeth II as Equerry?

Context paragraphs:
Sapphire Jubilee of Queen Elizabeth II: On 6 February 2017, the Sapphire Jubilee of Queen Elizabeth II, marking sixty-five years of her reign, occurred.  The longest-reigning monarch in British history, Queen Elizabeth II was the first British monarch to have a sapphire jubilee.  This Jubilee featured blue stamps from the Royal Mail, commemorative coins from the Royal Mint, and a reissue of an official 2014 portrait of Queen Elizabeth II by David Bailey.  In this official portrait the Queen wears sapphire jewellery which she received as a wedding present from her father.  The Jubilee also involved a gun salute at the Tower of London, a gun salute in Green Park, gun salutes in several other places around the United Kingdom, and the ringing of the bells in Westminster Abbey.  Theresa May, the Prime Minister of the United Kingdom, congratulated Queen Elizabeth II in regard to the occasion, saying in part, "I know the nation will join with me today in celebrating and giving thanks for the lifetime of service Her Majesty the Queen has given to our country and to the Commonwealth."

Adam Wise: Group Captain Adam Nugent Wise LVO MBE BA RAF (1943–2008) was a pilot, Equerry to Her Majesty Queen Elizabeth II, and Private Secretary and Equerry to Prince Andrew and Prince Edward from 1983 to 1987.

Timothy Laurence: Vice Admiral Sir Timothy James Hamilton Laurence {'1': ", '2': ", '3': ", '4': "} (born 1 March 1955) is a retired British naval officer and the second husband of Princess Anne, the only daughter of Queen Elizabeth II and Prince Philip.  Laurence was Equerry to the Queen from 1986 to 1989.

Golden Jubilee of Queen Elizabeth II: The Golden Jubilee of Queen Elizabeth II was the international celebration held in 2002 marking the 50th anniversary of the accession of Elizabeth II to the thrones of seven countries, upon the death of her father, King George VI, on 6 February 1952, and was intended by the Queen to be both a commemoration of her 50 years as monarch and an opportunity for her to officially and personally thank her people for their loyalty.  Despite the deaths of her sister, Princess Margaret, and mother, Queen Elizabeth The Queen Mother, in February and March 2002 respectively, and predictions in the media that the anniversary would be a non-event, the jubilee was marked with large-scale and popular events throughout London in June of the same year, bookended by events throughout the Commonwealth realms. Elizabeth attended all of the official celebrations as scheduled, along with her husband, the Duke of Edinburgh; over twelve months, the royal couple journeyed more than 40000 mi to the Caribbean, Australia, New Zealand, then around the United Kingdom, and wrapped up the jubilee year in Canada.  Numerous landmarks, parks, buildings, and the like, were also named in honour of the golden jubilee and commemorative medals, stamps, and other symbols were issued.

Elizabeth at 90: A Family Portrait: Elizabeth at 90: A Family Portrait is a 2016 television documentary film made to commemorate the 90th birthday of Queen Elizabeth II.  It was produced by the BBC and directed by John Bridcut, and narrated by Charles, Prince of Wales.  Aside from archive footage, the programme featured extensive footage shot by the Queen, Prince Philip, Duke of Edinburgh, Princess Margaret, King George VI and Queen Elizabeth the Queen Mother.  The footage had never been publicly shown and came from the Queen's private archive of homemade films.  The footage shown was interspersed with members of the British royal family commenting on the films.  The film featured contributions from the Queen, the Prince of Wales, Anne, Princess Royal, Prince William, Duke of Cambridge and Prince Harry, Lady Sarah Chatto, Prince Edward, Duke of Kent and Princess Alexandra, The Honourable Lady Ogilvy.

Peter Townsend (RAF officer): Group Captain Peter Wooldridge Townsend, (22 November 1914 – 19 June 1995) was a Royal Air Force officer, flying ace, courtier and author.  He was Equerry to King George VI from 1944 to 1952 and held the same position for Queen Elizabeth II from 1952 to 1953.  Townsend also had a romance with Princess Margaret.

Rosemary Pratt, Marchioness Camden: Rosemary Pratt, Marchioness Camden (9 May 1921 – 27 February 2004), born Cecil Rosemary Pawle, was a British socialite and artist, best known as the first wife of Group Captain Peter Townsend, who later became romantically involved with Princess Margaret of the United Kingdom.

Baron Plunket: Baron Plunket, of Newtown in the County of Cork, is a title in the Peerage of the United Kingdom.  It was created in 1827 for the prominent Irish lawyer and Whig politician William Plunket.  He served as Lord Chancellor of Ireland from 1830 and 1834 and again from 1835 to 1841.  His eldest son, the second Baron, was Bishop of Tuam, Killala and Achonry between 1839 and 1866.  He was succeeded by his younger brother, the third Baron.  He was a barrister.  His eldest son, the fourth Baron, served as Archbishop of Dublin between 1884 and 1897.  He was succeeded by his eldest son, the fifth Baron.  He was a diplomat and held office as Governor of New Zealand between 1904 and 1910.  His grandson, Patrick, the seventh Baron, was Equerry to both King George VI and Queen Elizabeth II.  He was succeeded by his younger brother, Robin who died in 2013 and was in turn succeeded by his nephew, Tyrone who was a Page of Honour to Queen Elizabeth II.

The Crown (TV series): The Crown is a biographical drama television series, created and written by Peter Morgan and produced by Left Bank Pictures and Sony Pictures Television for Netflix.  The show is a biographical story about the reign of Queen Elizabeth II of the United Kingdom.  The first season covers the period from her marriage to Philip, Duke of Edinburgh in 1947 to the disintegration of her sister Princess Margaret's engagement to Peter Townsend in 1955.  A second season has been commissioned, which is intended to cover the Suez Crisis in 1956 through the retirement of the Queen's third Prime Minister, Harold Macmillan, in 1963 following the Profumo affair political scandal.

Queen Elizabeth II Golden Jubilee Medal: The Queen Elizabeth II Golden Jubilee Medal (French: "Médaille du jubilé de la Reine Elizabeth II" ) or the Queen's Golden Jubilee Medal was a commemorative medal created in 2002 to mark the fiftieth anniversary of Elizabeth II's accession.  The Queen Elizabeth II Golden Jubilee Medal was awarded in Canada to nominees who contributed to public life.  The Queen's Golden Jubilee Medal was awarded to active personnel in the British Armed Forces and Emergency Personnel who had completed 5 years of qualifying service.

Supporting paragraphs: The Crown (TV series) Peter Townsend (RAF officer)
Answer: Princess Margaret