On December 11, ITV unveiled a new video featuring the Princess of Wales discussing the forthcoming televised special. The clip begins with a view of a magnificent Christmas tree and string lights outside Westminster Abbey, where the fourth annual carol service took place on December 6. It then shows Princess Kate assisting her youngest son, Prince Louis, who is 6 years old, in attaching a tag to the "Kindness Tree" outside the ancient abbey, with her elder daughter, Princess Charlotte, 9, looking on.

Princess Kate's Christmas Eve Message

In the video, 42-year-old Princess Kate says, "Join me this Christmas Eve for a special carol service to celebrate all those who have shown love, empathy and kindness in their communities this year." The snippet goes on to display the Princess of Wales entering the festive event with her husband, Prince William, and their children, Prince George, 11, Princess Charlotte, and Prince Louis. It also includes footage from the exciting night of the choir, performers Paloma Faith and Olivia Dean, ballet dancers, and children smiling. The video concludes with a photo of the Wales family standing together, holding programs and candles, from the front-row seats during the service, with Princess Kate sharing a sweet look with Prince Louis.

ITV's Christmas Eve Broadcast

"Together at Christmas – a chance to celebrate all those who have shown love, empathy and kindness in their communities this year," the ITV team wrote in a post with the video. "Watch Royal Carols: Together At Christmas on Christmas Eve at 7:30pm on @ITV and @ITVX." As in previous years, Princess Kate's December 6 carol event was filmed for broadcast on ITV in the UK on Christmas Eve.

Guest's Perspective

Jenny Powell, a community worker from Abergavenny, Wales, who was among the guests, tells PEOPLE in this week's issue. She says, "I know how hard it would be to do something like this, putting yourself out there when you may not be feeling 100 percent." This year's service was held with a poignant theme of love and empathy, as Princess Kate announced she was undergoing treatment for cancer in September. She completed chemotherapy, and this concert was her most significant appearance since.

Royal Family's Perspective

A source close to the royal household says, "Life-threatening illnesses bring a reconsideration of priorities. She and William have always made it clear that family is the most important thing." The Wales family's presence at the Together at Christmas carol service on December 6 was a significant event. Royal Carols: Together at Christmas airs on ITV and ITVX on Christmas Eve in the UK.