Kate Middleton's sweet birthday tradition with George, Charlotte, and Louis

Prince George, Princess Charlotte, and Prince Louis have a sweet tradition for their mum's birthday - and it will mean a great deal to Princess Kate after a difficult year

The Princess of Wales is celebrating her 43rd birthday today, and her children have found a special way to celebrate her.

The mum-of-three is set to spend the day at the Windsor family home, Adelaide Cottage, with Prince William by her side. And while the couple's three children will have to attend school as usual, they will likely present their mum with a very special gift upon their return.

Prince George, 11, Princess Charlotte, nine, and Prince Louis, six, are said to follow a sweet family tradition when it comes to Kate's birthday - and after such a difficult year for the Princess, it will be all the more poignant.

According to Closer, every year the siblings present Kate with a homemade collage of their favourite family photographs, including those they have taken themselves.

A source confirmed it has become "somewhat of a family tradition", with 2020 being the first year when pictures taken by the children themselves were also included.

The touching gesture will mean a great deal to Kate, who has a passion and talent for photography and loves nothing more than taking snapshots of her young family.

While the collage will no doubt be one of Kate's most treasured gifts, she is also likely to be spoiled with some luxury presents from her friends and family following her difficult year.

Royal expert Jennie Bond told OK! magazine: "This birthday is going to be memorable in so many ways – it will mark the start of a new and hopefully happier year and the end of one that has been brutal for the whole family."

Discussing what William likely has in store for his wife, she added: "For her husband and children, this will be an excuse to spoil her rotten and, even though it falls on a school day, I'm sure that's exactly what they'll do.

"I imagine they will shower her with gifts – perhaps some pampering products like luxurious bath oils and scented candles. Maybe William will buy her some silk pyjamas or cashmere jumpers – things that are soft on skin [after] treatment."

And the future King might even take to the kitchen to spoil his wife. "Even though he says he's not a very good cook, Catherine did tell Mary Berry that he's quite good at breakfasts so maybe a tray – complete with a rose – will arrive early for her," the expert suggested.

Prince William previously admitted that he isn't a pro in the kitchen. "Catherine is definitely the one who cooks, not me," he shared during the couple's appearance on A Very Berry Christmas back in 2019.

At one point during the festive program, British baking icon Mary Berry asked Kate: "Does William ever cook for you?"

"He sometimes does actually. He's very good at breakfast. University days, he used to cook all sorts of meals. I think that's when he was trying to impress me, Mary. Things like bolognese sauce and things like that," she said.

It comes after the Prince shared a loving and emotional message for his wife on social media in honour of her 43rd birthday, alongside a beautiful new photo.

Taken by Matt Porteous in Windsor last summer, the image shows Kate looking relaxed and smiling, with her hands in her jeans pockets and wearing a gingham scarf.

"To the most incredible wife and mother. The strength you've shown over the last year has been remarkable. George, Charlotte, Louis and I are so proud of you. Happy Birthday, Catherine. We love you. W," William wrote.