Who is Kate Middleton's 'shoulder to cry on'?

Princess Kate, 42, has faced health challenges this year.

But she has had a close confidant in her brother James Middleton, who celebrates his 37th birthday today, according to royal biographer Claudia Josephs

Businessman James, the youngest Middleton sibling, was the only immediate family member to publicly acknowledge Kate's cancer announcement, declaring, "Over the years, we have climbed many mountains together. As a family, we will climb this one with you too."

Claudia Josephs emphasised on the tight-knit bond between Kate and her siblings telling the Sun "The Middleton family has always been an extremely close-knit clan and they always turn to each other for support both in times of celebration and in strife.”

Josephs, the author of Kate: The Making of a Princess, notes the family's idyllic childhood and their strengthened connection since the Wales's move to Windsor: “They had an idyllic childhood, playing sport together, baking cakes and sliding down the stairs on a tray. And, since the Wales’s moved to Adelaide Cottage, in Windsor Home Park, they have become even closer.”

She adds that Kate often finds comfort with her family, including sister Pippa, 40, during difficult times: “Certainly, it was to the sanctuary of their childhood home that Kate fled when she broke up with William in 2007."