Monday marked a special day for the King's cousin, Lady Sarah Chatto, just days ahead of the coronation.
The painter and artist celebrated her 59th birthday on 1 May and is expected to be among the guests at the ceremony on Saturday, along with her older brother, David Armstrong-Jones, 2nd Earl of Snowdon.
Lady Sarah is the only daughter of the late Princess Margaret and her former husband, Antony Armstrong-Jones, who passed away in 2017.
She is married to British artist and former actor, David Chatto. The pair tied the knot in London in 1994, with Zara Tindall among their bridesmaids.
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The couple have two sons, Samuel and Arthur, born in 1996 and 1999 respectively.
Sam, who studied History of Art at the University of Edinburgh, now makes his own ceramics.
Meanwhile, Arthur, who also attended the University of Edinburgh, joined the Royal Marines last year.
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Lady Sarah and her husband joined King Charles and the Queen Consort at Windsor Castle on Easter Sunday earlier this month.
She looked elegant in a bold orange knit with a satin skirt, an oversized hat and pearls, for the church service at St George's Chapel.
See who else attended the Easter Sunday service in Windsor in the clip below...
The Chattos also attended the late Queen Elizabeth II's state funeral last September, as well as the Platinum Jubilee celebrations.
Royal fans have often noted that the Prince and Princess of Wales's daughter, Princess Charlotte, bears a resemblance to Lady Sarah Chatto in childhood photographs.
Charlotte, who is third in line to the throne, will celebrate her eighth birthday on Tuesday 2 May.