Prince Louis and Princess Charlotte at Kate Middleton’s Christmas concert on Dec. 8, 2023.Photo:Chris Jackson/Getty

The Dean of Westminster Abbey, The Very Reverend Dr David Hoyle, Prince William, Prince of Wales, Prince George of Wales, Prince Louis of Wales, Catherine, Princess of Wales and Princess Charlotte of Wales attend The “Together At Christmas” Carol Service at Westminster Abbey on December 08, 2023 in London, England.

Chris Jackson/Getty

AnotherPrince Louisouting, another adorable moment!

Kate MiddletonandPrince William’s youngest child joined his family at the thirdannual Christmas carol concertat Westminster Abbey on Friday evening, marking hisdebutat the holiday event.

Just like older siblingsPrince GeorgeandPrincess Charlotte, 5-year-old Louis joined the congregation in holding lit candles for the end of the service — and was caught blowing out his sister’s flame as they exited!

In a photo of the moment, Prince Louis leans over with puffed cheeks to blow out Princess Charlotte’s candle — and behind them, Princess Kate appears to catch his cheeky move.

Kate Middleton watches Prince Louis blow out Princess Charlotte’s candle at Christmas concert on Dec. 8, 2023.Chris Jackson/Getty

The Dean of Westminster Abbey, The Very Reverend Dr David Hoyle, Prince William, Prince of Wales, Prince George of Wales, Prince Louis of Wales, Catherine, Princess of Wales and Princess Charlotte of Wales attend The “Together At Christmas” Carol Service at Westminster Abbey on December 08, 2023 in London, England.

While most members of the congregation held both a candle and a program, Prince Louis focused solely on his candle!

This isn’t the first time Prince Louis has stolen the spotlight at a royal event. In May 2023, the little prince went viral for a photo that captured himyawningduring his grandfather King Charles' coronation.

Previously in June 2022, during Queen Elizabeth’s Platinum Jubilee, a photo circulated of the prince covering his ears and yelling as the Royal Air Force planes noisily passed overhead while he joined the royals on the Buckingham Palace balcony.

Louis is “a cheeky monkey— a typical third child,” someone who knows the family previously told PEOPLE. “It’s nice that the world got to see him enjoying himself.”

Queen Elizabeth, Prince Louis and Princess Charlotte in June 2022.Samir Hussein/WireImage

Queen Elizabeth II, Prince Louis of Cambridge, Princess Charlotte of Cambridge and Prince George of Cambridge during Trooping the Colour on June 02, 2022

Samir Hussein/WireImage

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Before heading into Westminster Abbey for the holiday event, George, Charlotte and Louis had an important task: mailing special letters. Children were encouraged to send Christmas cards and best wishes to other children who might be struggling this year. The trio headed over to a red mailbox outside the venue and dropped their letters inside before joining their parents for their entrance. According toroyal reporter Rebecca English, George, Charlotte and Louis all wrote their own cards.

Princess Charlotte, Prince Louis and Prince George attend Christmas concert on Dec. 8, 2023.Chris Jackson/Getty

Princess Charlotte of Wales, Prince Louis of Wales and Prince George of Wales post letters to Santa before The “Together At Christmas” Carol Service at Westminster Abbey on December 08, 2023 in London, England.

While Prince George, 10, and Princess Charlotte, 8, have accompanied their parents at royal events for several years, Prince Louis is only recently old enough for such outings. In 2019, George and Charlotte made theirChristmas Day debutalongside the royal family for their annual walk to church services — and last year, Prince Louisjoined for the first time!

Prince George, Princess Charlotte and Prince Louis attend Christmas concert on Dec. 8, 2023.Chris Jackson/Getty

Prince George of Wales, Princess Charlotte of Wales and Prince Louis of Wales attend The “Together At Christmas” Carol Service at Westminster Abbey on December 08, 2023 in London, England.

source: people.com