Kate, 41, will host the festive event at Westminster Abbey on 8 December. This year the concert will be dedicated to those who work to support babies, young children and families in communities across the UK.
Members of the royal family will also be among the guests at the Abbey.
The news sparked a huge reaction from royal fans on social media, and a couple have been wondering the same things.
"I hope that Prince Louis will join his siblings this year if they attend the Christmas Carol Service," one commented.
"Christmas Carol service will be so beautiful and lovely Christmas songs and everyone in good spirits. Hopefully Prince Louis and Prince George and Princess Charlotte will join this year's Christmas carol service with the royal family," another added.
It has not been confirmed by Kensington Palace whether Prince William and Kate's three children, Prince George, ten, Princess Charlotte, eight, and Prince Louis, five, will join the festivities this year.
George and Charlotte accompanied their parents for Kate's carol concert for the first time last year.
HELLO!'s Royal Editor Emily Nash says: "Prince Louis may well join his siblings at this year's Carol Service given he is a little older now and has more experience of being at public events. He managed to sit through most of his grandfather's coronation in May, so he may well be ready to return to the Abbey.
"Given this year's service will focus on Kate's Shaping Us campaign, it would be fantastic to see her own three children joining her and William at this very special event."
Over the past year, Louis has been seen at more major royal events, including the Christmas Day church service, Trooping the Colour, the King's coronation and his first official engagement with the Scouts with his parents and siblings in Slough in May 2021.
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Fans are also wondering whether the Princess of Wales will showcase her musical talents again at this year's Christmas carol concert.
In 2021, Kate played piano alongside Tom Walker performing his Christmas song, For Those Who Can’t Be Here.
The Princess, who has grade three piano and grade five theory, also made a surprise appearance during the opening performance of Eurovision back in May.
Singers Beverley Knight and Adam Lambert, multi-instrumentalist Jacob Collier, performer Freya Ridings and singer-songwriter James Bay will be among the entertainers at the 2023 service, which will be broadcast on ITV1 on Christmas Eve.
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