Kate Middleton sends rare personal message on her birthday

The Duchess of Cambridge is 40 on Sunday

The Duchess of Cambridge shared a very heartfelt message to social media on Sunday, as she celebrated her 40th birthday.

A post on the Cambridges’ official Instagram page featured one of her birthday photos by Paolo Roversi and was signed "C," indicating that it was a personal note from the Duchess herself.

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It read: "Thank you for all of your very kind birthday wishes, and to Paolo and the National Portrait Gallery for these three special portraits. C."

Fans were quick to react to the lovely message, with one writing: "You are simply stunning YRH," and another adding: "Happy Birthday, Duchess Catherine."

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A third sweetly commented: "I absolutely love all of the portraits Catherine! Thank you for sharing them. You are so beautiful, inside and out and I hope you are enjoying your special day so far."

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Kate released three stunning images in honour of her birthday, and they featured the Duchess as we've never seen her before.

The Duchess shared a sweet message for fans on social media 

She was photographed by the acclaimed photographer at the Royal Botanic Gardens, Kew, back in November.

In the portraits, the Duchess wears three exquisite gowns by Alexander McQueen, the British label that created her historic wedding dress.

In one photo, she paid tribute to her late mother-in-law Princess Diana as she wore her pearl drop earrings while in another, she teamed a striking red one-shouldered gown with diamond earrings on loan from the Queen.

Kate looked stunning in her 40th birthday portraits

Speaking about having the opportunity to take the photos, Paolo said: "Taking the portrait of Her Royal Highness, The Duchess of Cambridge, was a true honour for me, and a moment of pure joy.

"I was moved by her warmth and friendly welcome and enchanted by her shining eyes that reflected the loveliness of her soul and her smile showing the generosity of her heart.

"It was a profound and rich experience for me, an unforgettable moment. I have met a wonderful person, a person who, with her positive energy, can bring hope to the whole world."

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