Kate Middleton makes sad admission about cancer journey in rare comment during Christmas carol service

Kate Middleton, Princess of Wales, attended the Royal Carols: Together at Christmas carol service on 6 December, and opened up about her cancer journey.

Kate was present with her husband, Prince William, and their children, Prince George, 11, Princess Charlotte, 9, and Prince Louis, 6.

While there, Louis left a note on the Kindness Tree at Westminster Abbey addressed to his maternal grandparents, Carole and Michael Middleton, which read: "Thank you to Granny and Grandpa because they have played games with me."

42-year-old Kate chatted with musician Paloma Faith at the celebration, during which she said: "I didn’t know this year was going to be the year that I’ve just had", as reported by Channel 5.

Paloma responded: “The unplanned."

“The unplanned, exactly,” Kate agreed. “But I think lots of people this year have had such challenging times.”

In a statement, Kensington Palace stated in November: “This year’s service provides a moment to reflect upon the importance of love and empathy, and how much we need each other, especially in the most difficult times of our lives.

“The service will shine a light on individuals from all over the UK who have shown love, kindness and empathy in others in their communities, whether on a personal level with friends and family, through their work or as they selflessly give up their time through volunteering.”

Kate's appearance at the Together at Christmas carol service was the Princess' first major return to royal duties following her cancer diagnosis, which was followed by rounds of chemotherapy.

Kate attended the Royal Carols: Together at Christmas carol service (Max Mumby/Indigo/Getty Images)

The Princess of Wales is now cancer-free.

In a statement shared once she had completed chemotherapy, she said: "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.

The Princess was joined by her husband and children (Aaron Chown - WPA Pool/Getty Images)

"This time has above all reminded William and me to reflect and be grateful for the simple yet important things in life, which so many of us often take for granted. Of simply loving and being loved."

She added: "Although I have finished chemotherapy, my path to healing and full recovery is long and I must continue to take each day as it comes," she said, hinting at what's ahead.

"I am however looking forward to being back at work and undertaking a few more public engagements in the coming months when I can. Despite all that has gone before, I enter this new phase of recovery with a renewed sense of hope and appreciation of life."