Olympic cycling champion Sir Chris Hoy and Lindsey Burrow will be among the celebrities to join the Princess of Wales at her upcoming Christmas carol service.
Sir Chris, who is terminally ill with prostate cancer, will light a candle alongside Ms Burrow, the wife of former Rugby League star Rob Burrow who died in June after a battle with motor neurone disease.
The annual service aims to provide a moment of reflection about the importance of loved ones and comes as the princess returns to public duties after being treated for cancer this year.
Kate will deliver a Christmas message about the importance of love, she will describe as “the greatest gift we can receive”.
She wrote a letter for the 1,600 Westminster Abbey carol-goers, including members of the royal family, telling them “love is the light that can shine bright, even in our darkest times”.
Her message, featured with the order of service for the event on Friday, will say: “This Carol Service is a heartfelt celebration of every one of you, and a reminder that at Christmas, and throughout the year, we must all shine for each other.
“Because in times of joy and sadness, we are all each other’s light.”
The service will come near to the end of a difficult year for Kate, who revealed she had been diagnosed with cancer in March after undergoing abdominal surgery.
She underwent treatment, and in September said she was cancer-free. She has since gradually returned to public duties, with the service set to be one of her biggest come-back events.
Kate is expected to be joined by her family, husband the Prince of Wales, and their children Prince George, Princess Charlotte and Prince Louis.
Readings, linked to the theme of love and empathy, will be made by Prince William and a host of stars including actors Richard E Grant, Downton Abbey star Michelle Dockery, Sophie Okonedo, nominated for an Oscar for her role in the film Hotel Rwanda, and Olympic swimming champion Adam Peaty.
Kate said in her letter: “The Christmas story encourages us to consider the experiences and feelings of others. It also reflects our own vulnerabilities and reminds us of the importance of giving and receiving empathy, as well as just how much we need each other in spite of our differences.
“Above all else, it encourages us to turn to love, not fear. The love that we show ourselves and the love we show others.
“Love that listens with empathy, love that is kind and understanding, love that is forgiving, and love that brings joy and hope.
“It is this love which is the greatest gift we can receive. Not just at Christmas, but every day of our lives. Love is the light that can shine bright, even in our darkest times.”
Singers Gregory Porter and Paloma Faith will perform and pianist Rosey Chanas will play a specially composed piece, and the Westminster Abbey Choir will sing well known carols during a service combining the traditional and the modern.
The event will be broadcast as part of the programme Royal Carols: Together At Christmas, screened on ITV1 and ITVX on Christmas Eve, and it will feature three films about the stories of people and organisations who have inspired, counselled and comforted others in their times of need.