Family means everything to the Princess of Wales.
But she is also incredibly close to her family, the Middletons. Meet the clan in our video below!
So, she will be excited to celebrate a special event this weekend, when her younger brother turns 36 on Saturday 15 April.
Despite her busy royal schedule, Kate will likely find time to mark the happy occasion with her family – including James's wife of 18 months, Alizee Thevenet.
Kate was among the guests at the couple's nuptials in September 2021 – and was recently spotted in a previously-unseen photo taken at the evening reception.
Just last month, James paid tribute to his mum and his sisters in honour of International Women's Day.
He also previously wrote about how they had supported him following the devastating loss of his long-time pet, dog Ella.
"All the family came to say their goodbyes. I can't speak for them but I believe she influenced their lives too," he wrote. "Lupo, Catherine and William's dog, was one of Ella's puppies. My sister Pippa and her husband have a pup from Ella, as do other family members."
After Ella's passing, James attended therapy to get through the challenging time—and his sisters supported him there, too.
"My sisters came to some of my therapy sessions. They've always been there during difficult times and they were at my side during the hardest of times as well. For that, I am forever grateful," he wrote.
LISTEN: Want to hear more about the royal family? Check out the best of 'A Right Royal Podcast'