A post appeared on the Instagram profile of Kate Middleton and Prince William regarding this year's Christmas carol concert. The Duchess sent a special letter to guests in which she writes about "the most difficult times.

In the following months, the Duchess did not appear in public, focusing on treatment. However, by June, she slowly began to return to her duties. She graced events such as Trooping the Colour and the Wimbledon final with her presence.

Christmas may be a time for celebration, but this year, for Kate Middleton, it's also a moment to reflect. On Saturday, the Princess of Wales penned a poignant holiday message to the 1,600 guests of her annual "Together at Christmas" carol concert following a difficult year that saw her undergo chemotherapy treatment after a devastating cancer diagnosis .