Kate Middleton stuns a little girl with her reaction for inviting Prince George to birthday party

Prince William and Kate Middleton won hearts with their sweet gesture to a little girl who had invited Prince George to her sixth birthday party.

The Duke and Duchess of Cambridge sent a touching latter to a delighted mum after her daughter's stunning move.

The proud mom of six-year-old fairy shared the letter she received from Kate and William on Twitter, writing: “Something amazing for her to keep.”

It read: "The Duke and Duchess of Cambridge have asked me to thank you for your letter, in which you invite Prince George to your 6th Birthday party. I am sorry that it took so long to reply.

"Their Royal Highnesses were extremely grateful for your kind invitation. Having given careful consideration to the possibilities, however, I very much regret that Their Royal Highnesses reluctantly feel they have to decline.

"Nevertheless, I hope that you enjoyed your birthday.”

The letter continued: "The Duke and Duchess of Cambridge were immensely touched that you should take the trouble to write as you did to their son, Prince George. It really was most thoughtful of you and Their Royal Highnesses have asked me to send you their warmest thanks and best wishes."

Kate sent the heartfelt message to the woman's daughter who eagerly invited Prince George to her birthday party a few months prior. The woman who shared the heartfelt letter said it was “amazing” and something for her daughter to “keep” for years to come.