The Duke and Duchess of Cambridge's children are so excited for Christmas that they've already sent letters off to Santa.

According to an insider, Prince George, Princess Charlotte and Prince Louis "can't wait for Christmas" and want their parents to put up decorations already.

"It's their favourite time of the year... in fact, they've already written their list for Santa and are nagging William and Kate to put up the Christmas tree," the insider tells Us Weekly magazine.

This could be because grandmother Carole Middleton has already promised the trio that they could decorate her tree via video call.

“We may not be able to get together but, after a year like 2020, we need to remember what’s really important this Christmas," Kate Middleton's mom, who is also grandmother to 2-year-old Arthur, her daughter Pippa's son, wrote in a new Instagram post for her Party Pieces company.

“For me, what really matters is that my family feels connected," wrote Carole, 65. "I normally let my grandchildren help me decorate the tree. This year, I’ll ask them by video call to decide which decoration should go where. It may need to be tastefully rearranged later…!”

The trio also get a tree each to decorate in each of their rooms at grandmother Carole's house.

Space isn't an issue as she lives in a manor house with her husband Michael.

Explaining her reasoning, Carole shared it’s “so that they can decorate it themselves.”