Princess Catherine’s brother issued an emotional message on Sunday about his sister Princess Catherine. Exactly a week on from completing the Three Peaks Challenge together, James shared a photograph of the pair embracing at the end of the challenge.

He also penned an emotional message online, recalling how important the challenge was for his royal sister. He even spoke about how they had talked about climbing mountains while Catherine was in the hospital, showing just how close the siblings are. Taking to Instagram, James wrote: “I’m so incredibly proud of my darling sister.”

He continued: “Two years ago, I told you we’d climb this mountain together. We talked about climbing mountains while you were in hospital, and about the incredible healing power that nature can have for both the body and the mind.

“So it was such an honour to join you for your Three Peaks Challenge for the Royal Marsden Cancer Charity

“Seeing how far you’ve come is nothing short of inspiring. Your strength, resilience, and determination, all while being the most amazing mother, wife, daughter, and sister, inspire me and so many others every single day.

“Keep being exactly who you are. If you’d like to support or learn more about the Royal Marsden Cancer Charity, please visit the link in my bio.”

Catherine and James completed the challenge to raise money for The Royal Marsden.

This is where Catherine underwent her cancer treatment in 2024 after being diagnosed following a surgery.

The princess has been in remission since early 2025 and has since returned to royal duties, including an overseas royal trip.