Queen Elizabeth II's only niece Lady Sarah Chatto looked sombre as she attended the service at Westminster Hall following the Queen's procession on Wednesday.
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Lady Sarah, 58, who is the daughter of the Queen's late sister, Princess Margaret, appeared visibly upset as she joined members of the royal family to pay her respects to Her Majesty.
WATCH: Queen's children mount vigil around their mother's coffin
As per "royal mourning" guidelines, Sarah donned a flattering pleated skirt for the poignant occasion. She teamed her all-black ensemble with a hat, and finished off her look with some pearls and a pair of smart black heels.
READ: Lady Sarah Chatto's sweet nod to mother Princess Margaret on her wedding day
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Lady Sarah seen on Wednesday
The Queen's niece was joined by Princess Anne, as well as the Queen's other grandchildren, Prince William, Prince Harry, Princesses Beatrice and Eugenie, and their respective husbands, Edoardo Mapelli Mozzi and Jack Brooksbank, as well as Lady Louise Windsor and James, Viscount Severn.
King Charles III and Camilla, Queen Consort, the Princess of Wales, Meghan Markle, Sir Tim Laurence, Prince Andrew, the Earl and Countess of Wessex were also in attendance.
Lady Sarah shared a close bond with the Queen
Her late Majesty's coffin was placed in the historic Bow Room within her official London residence for one night, before the procession took place the following day to move her to Westminster Hall.
The coffin left Buckingham Palace at 2.22pm. Crowds watched as the cortege made the journey through central London - along Queen's Gardens, The Mall, Horse Guards and Horse Guards Arch, Whitehall, Parliament Street, Parliament Square and New Palace Yard.
The Queen's funeral is scheduled to take place on Monday 19 September at Westminster Abbey in what is expected to be an extremely emotional service.
The royal family is in mourning
Whilst the public are not able to attend the funeral, royal fans will be able to pay their respects at Westminster Hall where the late monarch will lie-in-state for four days.
After her funeral, Her Majesty will be laid to rest at the King George VI memorial chapel, the resting place of her parents and sister, King George VI and Queen Elizabeth The Queen Mother, and Princess Margaret.
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