Prince William and Princess Kate Are Prioritizing Their Children's "Happiness" Amid Kate's Diagnosis, Source Says

Prince William and Princess Kate are in a difficult place right now, since the princess is dealing with a cancer diagnosis. Still, their first priority remains their children, according to one source—and this was especially true as Prince Louis celebrated his 6th birthday on Tuesday.

"William and Kate are trying to keep things as normal as possible for their children’s sake," the source told OK!. "They don’t want Kate’s diagnosis to overshadow the children’s lives and their happiness and [they] are very much their priority."

Speaking to the publication on April 23, the insider added, "They [William and Kate] will celebrate Louis’ birthday with his friends as usual and make a special effort to celebrate their anniversary together the weekend afterwards in Norfolk."

The Waleses will celebrate 13 years of marriage on April 29. Meanwhile, to mark Louis' big day, they shared an exclusive photo of the little boy looking extremely happy on Instagram. The picture was taken by his mother.

Last month, Kate sadly revealed in a two-minute video that she had been diagnosed with cancer.

As part of her message, the princess had already made it clear that hers and William's children were their priority during her illness.

"This, of course, came as a huge shock," she said of the diagnosis. "Most importantly, it has taken us time to explain everything to George, Charlotte, and Louis, in a way that's appropriate for them, and to reassure them that I'm going to be OK."

Prince George is 10 years old, while Princess Charlotte is 8.