Grace Barrett introduced herself to Charlotte before explaining why she would be at the Castle

Princess Kate and Prince William have posted a touching handwritten letter written by a 10-year-old, addressed to Princess Charlotte, on their Instagram story.

This post comes just one day after an investiture ceremony took place at Windsor Castle with King Charles.

The message was written by Grace Barrett, 10, whose mother, Carly Barrett, and grandmother, Alison Madgin, were honoured by the King during the ceremony.

Mrs Madgin and Mrs Barrett run “Samantha’s Legacy”, a charity that raises awareness of and works to prevent knife crime, while also supporting bereaved families.

The Prince and Princess of Wales’s post, uploaded to the couple’s official Instagram account, included a video of King Charles presenting an honour to Mrs Barrett, who was wearing a green dress.

Mrs Barrett was accompanied by Mrs Madgin in the video, which Kate and William placed below Grace’s neatly penned note to the young Princess Charlotte.

Grace introduced herself to Princess Charlotte before explaining why she would be at Windsor Castle.

“My name is Grace Barrett, and I’m 10 years old. Just [like] you!” she wrote.

Princess Charlotte receives touching letter from young girl, 10, ahead of Windsor Castle visit

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She went on to explain that she would be visiting “on [9th] December with my mum, Carly Barrett, who is being [awarded] an MBE for her special work helping people affected with crime.”

Grace’s mother, Mrs Barrett, was recognised for her work supporting families impacted by violent crime.

The 10-year-old also proudly noted that her grandmother, Mrs Madgin, was receiving a medal on the same day.

Mrs Madgin has been a prominent campaigner following the tragic loss of her daughter, Samantha, and has worked extensively to improve support for victims’ families.

Grace Barrett’s letter to Princess Charlotte could be seen on the Waleses’ Instagram story

 | INSTAGRAM: PRINCE AND PRINCESS OF WALES

“I’m really proud of them both and feel honoured to be going with them,” Grace wrote in her message.

The Prince and Princess of Wales added their own warm acknowledgement beneath the letter.

Kate and William wrote: “Thank you to Grace Barrett for her letter to Princess Charlotte about all the brilliant work her mum and grandmother do.”

The post reflects the continued emphasis by Prince William and Princess Kate on highlighting positive community stories and the achievements of ordinary families contributing to public service.

Alison Madgin (L) and her daughter Carly Barrett, from ‘Samantha’s Legacy’, an organisation helping educate young people about the dangers of knife crime, pose after being made Members of the British Empire (MBE) by King Charles

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It also marks a rare public moment linking Princess Charlotte, 10, to individuals recognised for their work supporting vulnerable people.

The Waleses’ decision to share the note underscores their ongoing efforts to celebrate those working to improve lives across the UK.

In addition, it shows Kate and William encouraging engagement between young people and the monarchy.