BERLIN, GERMANY - JUNE 05: Princess Anne In Berlin, Germany On A Visit From 5-9 June 1973 (exact Day Date Of Photograph Not Certain) (Photo by Tim Graham Photo Library via Getty Images)

LONDON, UNITED KINGDOM - AUGUST 24: Britain's Princess Anne and her fiance Captain Mark Phillips, attend the London premiere of the film "Jesus Christ Superstar" 24 August 1973, shortly after her 23rd birthday, and on the couple's first public engagement. (Photo credit should read AFP/AFP via Getty Images)

KIEV, RUSSIA - SEPTEMBER 06: Princess Anne, Dressed Casually In Shirt And Jeans, In Kiev, Russia During Her Visit 5-11 September 1973 (Photo by Tim Graham Photo Library via Getty Images)

SANDHURST, UNITED KINGDOM - AUGUST 01: Princess Anne Attending A Passing Out Parade At Sandhurst Military Academy Wearing A Dress She Was To Wear Again Eleven Years Later With An Extended Hemline. (date Not Certain) (Photo by Tim Graham Photo Library via Getty Images)

STAMFORD, UNITED KINGDOM - SEPTEMBER 13: Princess Anne At Burghley Horse Trials. The Princess Is Dressed To Compete In The Dressage Section Of The Competition. (Photo by Tim Graham Photo Library via Getty Images)

GREAT SOMERFORD, UNITED KINGDOM - MAY 06: Princess Anne With Her Husband, Mark Phillips, Just Weeks Before The Arrival Of Their Daughter Attending The Wedding Of Her Sister-in-law. (exact Day Date Not Certain) (Photo by Tim Graham Photo Library via Getty Images)

UNITED KINGDOM - JUNE 21: Princess Anne At A Village Fete In Great Somerford. (Photo by Tim Graham Photo Library via Getty Images)

Princess Anne, the Princess Royal, in Berlin for the Queen's Birthday Parade, June 1973. (Photo by Serge Lemoine/Getty Images)

(Original Caption) London, England: As she grows up, Princess Anne of Great Britain takes on added responsibilities. She is wearing a smart hat and colorful red coat in the afternoon to perform the opening ceremony of the new Police Cadet Training School.

PYEONGCHANG-GUN, SOUTH KOREA - FEBRUARY 08: Princess Anne, Princess Royal attends the IOC President's Dinner ahead of the PyeongChang 2018 Winter Olympic Games on February 8, 2018 in Pyeongchang-gun, South Korea. (Photo by Andreas Rentz/Getty Images)

Princess Anne, the Princess Royal, in Africa, February 1971. (Photo by William Lovelace/Daily Express/Getty Images)

Princess Anne on her wedding day with her husband Mark Phillips, her younger brother Prince Edward, and cousin Lady Sarah Armstrong-Jones. (Photo by © Hulton-Deutsch Collection/CORBIS/Corbis via Getty Images)

Princess Anne at Horse Trials with members of the Royal Canadian Mounted Police, UK, 1968. (Photo by Jeremy Fletcher/Getty Images)

LONDON, ENGLAND - JUNE 10: Princess Anne, Princess Royal attends a National Service of Thanksgiving as part of the 90th birthday celebrations for The Queen at St Paul's Cathedral on June 10, 2016 in London, England. (Photo by Mark Cuthbert/UK Press via Getty Images)

ASCOT, ENGLAND - JUNE 17: Princess Anne With Lord Porchester (later Earl Carnavon), The Queen's Racing Manager, At Royal Ascot June 17-20 1980 (Photo by Tim Graham Photo Library via Getty Images)

WINDSOR, ENGLAND - MAY 10: Princess Anne, Princess Royal enjoys the sun at the Royal Windsor Horse Show 2019 on May 08, 2019 in Windsor, England. (Photo by Chris Jackson/Getty Images)