But one part of the video that stood out to Judi was a touching moment between the Princess, her husband Prince William and their children, Prince George, Princess Charlotte and Prince Louis. She commented: “But the main bulk of this video shows Kate not just surrounded by love and care but also offering it.

“When she and William sit or lie on a blanket on the ground it’s her arm around his shoulder or her head higher as he falls in to kiss her cheek. Kate curls into William in a gesture of total adoration and he clasps both her hands and pats them in a gesture of reassurance but there are times when, in his shorts and sandals, he looks like a bigger version of George who hugs Kate in a cuddle as she kisses his head.”

Despite the seriousness of Kate’s condition and the rare update, Judi admits there are some moments which clearly demonstrate Kate’s playful attitude with her children. “This is a poignant video but there are moments when the body language is all about play and fun too,” she said, adding: “If the love signals between William and Kate are a revelation so are George, Charlotte and Louis’s expressions of spontaneous, confident playful fun as they run up to the camera to pull faces in turn.

“One pose shows the family sitting in a row with Kate between her husband and daughter, with Charlotte’s arm on one of Kate’s legs and William’s hand on the other in a ritual of mutual and careful protection from both husband and daughter. But then we also get to see William roaring off to play cricket with the kids or even laying on Kate as they all form a rolling bundle of love between the sand dunes.”

Judi commented: “‘Out of darkness comes light’ is one of Kate’s more regal-sounding messages and on cue, a butterfly takes off from her hands in what is hopefully a positive symbolic moment.” In her update, Kate said: “As the summer comes to an end, I cannot tell you what a relief it is to have finally completed my chemotherapy treatment.

“The last nine months have been incredibly tough for us as a family. Life as you know it can change in an instant and we have had to find a way to navigate the stormy waters and road unknown. The cancer journey is complex, scary and unpredictable for everyone, especially those closest to you. With humility, it also brings you face to face with your own vulnerabilities in a way you have never considered before, and with that, a new perspective on everything.”

She added that the time has reminded both herself and the Prince of Wales to reflect and “be grateful for the simple yet important things in life,” which some often take for granted. “Despite all that has gone before, I enter this new phase of recovery with a renewed sense of hope and appreciation of life,” she continued. The Princess concluded: “To all those who are continuing their own cancer journey – I remain with you, side by side, hand in hand. Out of darkness, can come light, so let that light shine bright.”