Kate Middleton Speaks Out After Surprise Trip to the Ballet Post-Chemotherapy: 'Moving and Inspiring'

Kate Middleton had a day at the ballet two weeks after announcing that she completed chemotherapy treatment.

On Sept. 26, the Princess of Wales privately attended a matinee performance of Giselle by the the English National Ballet at Sadler's Wells Theatre in London. PEOPLE understands that Kate enjoyed the performance so much that she wanted to share a personal message about it.

"Congratulations and thank you to @ENBallet and @Sadlers_Wells for the wonderfully powerful, moving and inspiring performance of Akram Khan’s Giselle. Creativity at its best!," the Princess of Wales wrote on X, posting a photo of artists on stage in the ballet.

Princess Kate, 42, signed the post "C," using the shorthand for the first initial of her full name as she and her husband Prince William are known to do when messages come directly from them.

While she isn't Royal Patron of the English National Ballet (Queen Camilla holds that role), Princess Kate is known to have a keen interest in ballet and has privately taken her daughter Princess Charlotte, 9, to performances in the past. 

The Princess of Wales' latest under-the-radar ballet outing comes two weeks after she announced in a video message on Sept. 9 that she completed chemotherapy treatment. 

Princess Kate shared in March that she was receiving treatment for cancer and has been outside of the limelight for much of this year to privately prioritize her health.

"Doing what I can to stay cancer free is now my focus. 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," Princess Kate said in part in the message, which was interspersed over an intimate video of her and Prince William with their children Prince George, 11, Princess Charlotte, and Prince Louis, 6, 

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

On Sept. 17, the Princess of Wales made her first official work engagement since finishing chemotherapy when she held a meeting for her early childhood development project at Windsor Castle. The meeting marked her first Court Circular entry, the official record of engagements carried out by working royal family members, for 2024.

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It's understood that the princess met with her key aides and those who run her Centre for Early Childhood, a branch of The Royal Foundation she shares with William, during her meeting in Windsor last week.  

The Princess of Wales started working from home in the early summer, and is thought to hope to attend the Remembrance Day service on Nov. 10. 

Kate is also looking ahead to her annual carol concert in December, and held a meeting with her team from Kensington Palace and the Royal Foundation on Sept. 24 to discuss the plans for the fourth annual service which highlights and thanks causes close to her and William's hearts.