Despite being one of the lesser-known members of the royal family, Lady Sarah Chatto shared a special bond with the late monarch and frequently joins the Firm for key events.
And on Monday, she was spotted attending the late monarch's poignant state funeral at Westminster Abbey.
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Lady Sarah gained popularity after her appearance in the BBC documentary Elizabeth at 90: A Family Tribute, in which she captivated viewers with her down-to-earth nature and evident affection for the Queen.
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As the daughter of Princess Margaret and Antony Armstrong-Jones, Sarah is 28th in line to the throne and the Queen's only niece. However, she prefers to maintain a life out of the royal spotlight with her husband Daniel Chatto and their two sons, Samuel and Arthur.
Nonetheless, Sarah maintains a close relationship with the senior royals and reportedly enjoyed a special bond with Her Majesty.
The respect and affection she had for the monarch was clear to see in the BBC documentary in honour of Her Majesty's 90th birthday in 2016.
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Lady Sarah Chatto was spotted at the Queen's state funeral
The Queen is said to have "adored" Sarah, and used to allow her niece to accompany her to her favourite hideaway, Craigowan Lodge, in Aberdeenshire. The pair grew closer after the death of Princess Margaret in 2002, with whom the Queen shared an incredibly strong bond.
Of all her cousins it is Prince Charles who Sarah is said to remain closest to. The pair are said to enjoy spending downtime painting together at Balmoral when the opportunity arises. Sarah was also a chief bridesmaid at Charles' wedding to Princess Diana and is a godmother to their son Prince Harry.
The 58-year-old gained popularity following her appearance in a BBC documentary
Such is Sarah's popularity within the royal family, she was also selected to act as a godmother to Prince Edward's daughter Louise and the Duke of Gloucester's daughter Rose.
Sarah and her husband David Chatto
Sarah grew up in Kensington Palace with her older brother David and their parents, who divorced when she was just 13. As a teenager, she attended Bedales boarding school in Hampshire, where she cultivated her passion and talent for art.
The pair married in 1994
Following her graduation, she worked as a wardrobe assistant on Heat and Dust, where she met her husband Daniel Chatto, who had a small role in the film.
The couple shunned a lavish royal wedding in favour of a low-key service at St Stephen's Walbrook church in July 1994, with Sarah wowing in a Jasper Conran gown and the Snowdon Floral Tiara.
Still happily married, the couple live in Kensington and are parents to two sons - Samuel, 25, and Arthur, 23. Both sons studied at Eton before attending the University of Edinburgh.
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