Kate Middleton's hidden gesture in birthday photo sends bold message after 'brutal year'

William, the future King, shared a striking new photo of his wife in honour of her birthday - and, according to an expert, the black and white image sends out a strong message

Prince William has delighted royals by sharing a previously-unseen photograph of his wife Princess Kate in honour of her 43rd birthday.

The future King posted the snapshot on social media, alongside a very personal message which reads: "To the most incredible wife and mother. The strength you’ve shown over the last year has been remarkable. George, Charlotte, Louis and I are so proud of you. Happy Birthday, Catherine. We love you. W."

The striking black and white image shows the princess looking relaxed and happy as she poses with her hands in her pockets, with a gingham scarf hanging loosely from her neck and a blazer over a white shirt with the sleeves on both rolled up.

And according to body language expert Judi James, Kate makes a hidden gesture in the snap that shows her "confidence and resilience".

Judi told the Mirror: "This stylish, sassy and even slightly tongue-in-cheek pose shows Kate shot in monochrome to give a fashion-spread look in the wake of her previous more ethereal, pensive poses recently.

"Her sleeves are folded back and her fingers are elegantly stuffed into the pockets of her jeans with that gesture, plus the way it pushes her elbows slightly out to create an upturned V shape under her armpits, create the look of almost 'ready for anything' confidence and resilience."

The expert continued: "Her eyes look to the side and it's here her emotions are expressed rather than the mouth smile, which is her perfect, regal version. Her eye expression looks playful, with one brow slightly raised to suggest she's laughing and communicating with someone off-camera."

The new picture of Kate was taken by Matt Porteous in Windsor last summer - and he was among those to publicly send birthday wishes to the Princess. "Happy Birthday Catherine, wishing you a wonderful year ahead surrounded by family and loved ones," he wrote alongside the Instagram post.

William wasn't the only royal to celebrate Kate's special day. King Charles also paid a touching tribute to his 'beloved daughter-in-law.

The official Royal Family social media accounts shared a beautiful snap of the Princess beaming at Sandringham on Christmas Day as she collected countless bouquets of flowers from wellwishers. The heartwarming picture was accompanied with a message saying: "Happy Birthday to The Princess of Wales!" along with a birthday cake emoji.

Another royal expert, meanwhile, has suggested that William's touching personal message for his wife signals a new era for the royals.

Royal historian Dr Tessa Dunlop told the Mirror the 'breathtaking' photo and message is proof that long gone are the days of the royals maintaining a stiff upper lip and avoiding public displays of affection.

She explained: "Black and white, timeless and yet contemporary, the portrait photograph released to celebrate the 43rd birthday of the Princess of Wales is breathtaking, likewise the message that accompanies it. Authored by William, with the tell-tale W sign-off, he shares his great admiration for a ‘most incredible wife.’ And the Prince goes even further, speaking for him and his children, William publicly reaffirms their adoration for Catherine in three simple words: 'We love you.'

"Statements don't come much more powerful than that. Gone are the days when royally kept their distance and avoided overtly sentimental displays of affection; William is letting everyone know just how proud he is of his wife, and likewise what they have achieved together. Contrary to the monarchy's reputation in recent years, here is a functional family that can face down adversity together."