Catherine, Princess of Wales, and Princess Charlotte perform piano duet for Christmas carol service

Catherine, Princess of Wales, and her daughter Charlotte played a festive piano duet that aired on Wednesday as part of an annual Christmas service celebrating "love in all its forms," according to Kensington Palace.

British television viewers saw the "special musical moment" between Catherine and Princess Charlotte on Christmas Eve, the palace said in a statement, adding that the piano recital was recorded last week at Windsor Castle.

The royal mother and daughter performed Holm Sound by the Scottish producer Erland Cooper, a composition that they "enjoy playing together at home," the palace statement added.

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Cooper wrote the song for his mother, to reflect values including "nature, connection and togetherness."

The clip formed the opening sequence of the "Together at Christmas" concert, which is hosted by the Princess of Wales at Westminster Abbey, in London, and broadcast annually in the United Kingdom on December 24.

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In 2021, the princess hosted the first service to honor those who made a meaningful impact on their local communities at the height of the Covid-19 pandemic.

This year's extravaganza was filmed at the Abbey on December 5, and spotlit folks from all over the UK who have "dedicated or volunteered their time to be present with others, led initiatives that bring people in their community together, or offered a helping hand to those around them," the palace said in a statement.

On the night, the majestic, candle-lit Abbey was filled with 1,600 people connected by the "love and compassion" that "binds us all at Christmas and all year round," the palace statement added.

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British woodland trees threaded with fruits, berries and Christmas trees woven by the horticulturalist Jamie Butterworth lined the footsteps of the Abbey to create a "magical wonderland for guests from the moment they arrive."

After the service began, carols sung by the prestigious Westminster Abbey choir rang out inside the halls of the Gothic church.

A selection of British artists, including Hannah Waddingham, Griff and Katie Melua delivered musical performances, while speakers including the Prince of Wales, Kate Winslet and Chiwetel Ejiofor delivered poignant readings – all tied by the theme of "love, compassion and connection."

Supported by the prince and princess's Royal Foundation charity, the show also featured a special performance by young people from Platinum Performing Arts, an organisation based in the British capital.

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Organisers also staged 15 other "Together at Christmas" community carol services across the UK – including in Manchester, the Isle of Wight and Dyfed, in southwest Wales.

The princess has steadily returned to royal duties since being diagnosed with cancer last year. In September 2024, she announced that she had completed chemotherapy and was "doing what I can to stay cancer free."