Kate's 'deeply personal letter' to the family of murdered Londoner Sarah Everard

Kate Middleton has penned a deeply personal letter to the family of Sarah Everard, the young UK woman who was murdered earlier this month.

Two weeks ago, the Duchess of Cambridge joined mourners at a memorial for Everard, who vanished while walking home in London on March 3.

She arrived with a bouquet of yellow daffodils, taken from the gardens of Kensington Palace, and laid them at the site.

Now, the royal has reportedly reached out to Everard's family to share her sympathy for their unimaginable loss.

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"Kate's letter was deeply personal and heartfelt, she expressed her absolute sadness at what Sarah's family and loved ones are going through," a source told the Daily Mirror.

"She said she knows that no words can change what happened but that she wanted to let them know that they and Sarah are in her thoughts.

"This was a private matter to her, and she wanted to show unity with everyone else who shares these feelings."

A Kensington Palace spokesperson said they would not comment on private correspondence.

No official details about the alleged letter have been released, but Everard's death is said to have affected Kate deeply.

The duchess used to share a flat in the London suburb of Chelsea with her sister Pippa, less than 5km from Clapham, where Everard was last seen.

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The future queen "remembers what it felt like to walk around London at night before she got married", royal sources close to Kate said.

Everard's murder rocked the city of London, and the world, prompting thousands of other women to share their own scary stories about encounters that could have ended violently.

Women took to social media to speak about times they'd been approached by strange men on the street, assaulted or even attacked.

Shortly after her murder made headlines, a six-word text went viral as it showed the sad reality for many women around the world.

"Text me when you get home," summed up the fear women were – and still are - experiencing in the wake of Everard's death.