Prince William has honored “the most incredible wife and mother” with a heartfelt birthday message.

A new photograph of Princess Kate was released today to celebrate her 43rd birthday, accompanied by a rare personal message from her husband, Prince William.

The previously unseen photo, captured last summer in Windsor by photographer Matt Porteous, was shared with the public.

In the post, William praised “the most incredible wife and mother” and said, “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.”

Typically, Kate’s birthday isn’t marked with a message from William or a new photo release. However, it’s believed William chose to commemorate the day following Kate’s challenging year undergoing cancer treatment.

Earlier on Thursday, King Charles and Queen Camilla also extended birthday wishes to Kate through their social media, posting a photo taken on Christmas Day.

The royal family has adopted a more personal approach to social media updates over the past year, opting to share news on their own terms.

Kate publicly shared her cancer diagnosis in an emotional video, later revealing she had completed her chemotherapy in a short film featuring her family.

For Prince William’s birthday in June, Kate reciprocated with a personal message, writing: “Happy birthday Papa, we all love you so much! Cx.”