The Queen's official Trooping the Color birthday parade took place earlier on June 2, with the monarch, 96, joined by several members of the royal family, including her Cambridge great-grandchildren and two youngest grandchildren, in honor of her Platinum Jubilee.
The Duke of Kent was also by Her Majesty's side for the parade in the Castle's Quadrangle in his role as Colonel of the Scots Guards – the Queen's Colour of F Company Scots Guards were trooped at this year's parade.
Upon the return of the Household Cavalry Mounted Regiment and the Guards, the Queen took the salute from the balcony of Buckingham Palace with the Duke, Prince Edward.
The royal is the Queen's first cousin through their fathers, Prince George, Duke of Kent and King George VI.
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The 85-year-old was born on 9 October 1935 in London as the eldest child of the late Prince George and Princess Marina of Greece and Denmark. Prince Edward also has two younger siblings, Princess Alexandra, 84, and Prince Michael of Kent, 78.
He has held the title of Duke of Kent since the age of six, after the death of his father in a plane crash in 1942.
Prince Edward and Katharine on their wedding day with the royals
Edward married Katharine Worsley on 8 June 1961 at York Minster with the bride wearing a wedding dress designed by John Cavanagh, which was made of 237 yards of French-made diaphanous white silk gauze and featured a 15-foot double train. Katharine's white tulle veil was secured with the Kent Diamond and Pearl Fringe Tiara.
The Queen and the late Duke of Edinburgh's daughter, Princess Anne, was also given a starring role as a bridesmaid at the nuptials.
READ: The Queen's cousin the Duke of Kent's modest home revealed
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The Duke and Duchess of Kent pictured in 2013
Prince Edward and Katharine have three children, George Windsor, Earl of St Andrews, Lady Helen Taylor and Lord Nicholas Windsor, born in 1962, 1964 and 1970 respectively.
The couple, who split their time living between Wren House Kensington Palace and Oxfordshire, also have ten grandchildren.
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Edward, who is 40th in line to the throne, carries out engagements on behalf of the Queen and is involved with over 140 charitable organisations.
He was also among the 30 guests in attendance at Prince Philip's funeral in April.
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