WATCH: How the Queen's funeral unfolded
The very special accessory was created especially for her nuptials to Daniel Chatto in 1994 - the Snowdon Floral Tiara. It was made using three diamond brooches that were originally a wedding gift to her mother Margaret from her husband Antony Armstrong-Jones, the First Earl of Snowdon, in 1960.
The floral brooches feature a series of sparkling leaves and petals which were particularly striking when they were combined by Wartski to form the tiara.
The Queen's sister was pictured wearing the brooches on several occasions before her daughter's nuptials, including to the Ascot races in 1987. Lady Sarah also wore the brooches to her mother's funeral in February 2002.
Lady Sarah Chatto wearing the Snowdon Floral Brooches
Lady Sarah Chatto and her brother Earl Snowdon were among the group to pay their respects to their aunt. Sarah is 27th-in-line to the throne and was the Queen's only niece.
However, she prefers to maintain a life out of the royal spotlight with her husband Daniel 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.
Lady Sarah wore a diamond tiara made from her mother's brooches
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.
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.
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