Will’s touching tribute to his duchess in denim

With her wide smile and confident pose, it is a birthday portrait that proves what a difference a year makes.

Just a week after she turned 42 last year, the Princess of Wales was taken into hospital for abdominal surgery, after which doctors found cancer had been present.

Now Prince William has praised his “incredible” wife for the bravery she has shown over the gruelling period in an unprecedented public birthday message.

Yesterday he posted a new photograph of Kate, taken at Windsor last summer, which captures her joy at completing a course of preventative chemotherapy.

While images issued by Kensington Palace recently have largely been taken out and about in the countryside with her family, this powerful black-and-white portrait — by family favourite Matt Porteous — shows the princess alone in self-assured, casual mode, hands in the pockets of her jeans, wearing a jacket, checked scarf and Diana’s engagement ring.

In a notably emotional message, William wrote: “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.”