Prince George, Princess Charlotte and Prince Louis Support Mom Kate Middleton at Christmas Concert

Prince George and Princess Charlotte made their debut at the holiday event last year, but Prince Louis joined his family for the first time

Prince George, Princess Charlotte and Prince Louis are getting in the Christmas spirit.

The three young royals joined Kate Middleton and Prince William, both 41, at the third annual Christmas carol concert at Westminster Abbey, hosted by the Princess of Wales.

Before making their way inside, Prince George, 10, Princess Charlotte, 8, and Prince Louis, 5, made an important stop. They walked over to a red mailbox outside Westminster Abbey and placed envelopes inside. This year, children were encouraged to send homemade Christmas cards to other kids who might be struggling this year. According to royal reporter Rebecca English, George, Charlotte and Louis all wrote their own cards.

Related: See the Royals' Holiday Cards Through the Years

Prince Louis then held hands with Prince William and Princess Charlotte held hands with Princess Kate as they headed inside.

While Prince George and Princess Charlotte made their debut at the event last year, Prince Louis joined in the fun for the first time, making his debut at the festive night out.

Prince George, Princess Charlotte and Prince Louis weren't the only members of the royal family's next generation in attendance. Princess Beatrice brought her stepson Christopher Woolf (known by the nickname Wolfie!), and Peter Phillips' two daughters — Savannah and Isla — also tagged along. Lord Frederick Windsor and Sophie Winkleman also brought their children.

The event was specially geared towards children this year. The Christmas concert — featuring performances by Westminster Abbey's choir, Adam Lambert, Beverley Knight and more as well as a reading given by Prince William — is linked to Princess Kate’s Shaping Us campaign, which focuses on her mission to support children during the early years of their lives. The palace said the event was organized to “thank all those who work to support babies, young children and families in our communities across the U.K. and a celebration of the golden opportunity that the birth of a new baby brings."

After the service, Princess Kate and Prince William with their children followed the clergy in the processional out of Westminster Abbey, all holding lit candles.

The event will be broadcast as part of Royal Carols: Together At Christmas, airing on ITV1 and ITV X on Christmas Eve.

Prince George and Princess Charlotte made their debut at the holiday event supporting their mom last year. Wearing perfectly coordinating outfits, George, Charlotte, William and Kate headed inside the venue and sat together for the service.

Although all three of Prince William and Princess Kate's children stayed home when Kate hosted the first event in 2021, they're now regulars at Christmas events with the royal family. In 2019, Prince George and Princess Charlotte made their Christmas morning debut alongside the royals for their annual walk to church services — and last year, Prince Louis joined for the first time!

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The Prince and Princess of Wales' three children are also likely participating in holiday festivities at their new school, Lambook, where they started in September 2022.

According to the school's website, "Christmas festivities and opportunities make it even more special for our pupils, with every single child performing in a Christmas event, including Christingles, Nativities, Pre Prep House singing competitions and of course, our end of term Carol Service."

Earlier this month, Lambrook School started the Christmas season with an Advent service complete with a choir performance and nativity scene.

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