It happened on a quiet Thursday afternoon in late October 2025, inside the private family apartments at Windsor Castle. The children had just come home from Lambrook School, uniforms still on, cheeks flushed from the autumn wind. They were supposed to be doing homework. Instead, they overheard the conversation that no child should ever have to hear.

King Charles, voice cracking, had pulled Prince William aside in the Crimson Drawing Room. The latest scans from Kate’s ongoing cancer treatment had come back worrying. Doctors were talking about “aggressive new protocols,” possible surgery, and weeks of isolation. William, white as parchment, repeated the words like a man underwater: “She’s going to be sicker before she gets better.”

George (12), Charlotte (10), and Louis (7) were never meant to hear it. They were playing in the adjoining sitting room, supposedly distracted by tablets and Lego. But children hear everything.

For almost ten minutes there was silence. Then the three of them disappeared.

No one noticed at first. Nannies assumed they were in the playroom. William and Charles were too lost in their own grief to count heads. Security cameras later revealed what happened next, and when the footage was shown to the King two days later, even he (the man who once said he doesn’t cry) had to turn away.

The children didn’t run to their rooms to cry. They marched straight to Adelaide Cottage, their family home on the Windsor estate, using the secret tunnel the Wales children have used for generations. George carried a cardboard box. Charlotte clutched a fistful of crayons and her favourite gel pens. Louis dragged his beloved stuffed tiger, Winks, by one ear.

They locked themselves in Kate’s private dressing room (the one place they knew no one would disturb) and got to work.

For four straight hours they created something no royal protocol could ever teach them.

When William finally realised they were missing and sprinted home in blind panic, he found the door barricaded with a child-sized chair. He was about to break it down when George’s calm voice came through:

“Daddy, don’t come in yet. We’re nearly finished. It’s for Mummy.”

Inside, the carpet was covered in paper, glitter glue, and crumpled drafts. On Kate’s dressing table sat the finished masterpiece: a handmade book almost 50 pages long titled “Mummy’s Get-Better-Soon Bible – By Your Three Little Warriors”.

Every single page was a promise, a memory, and a weapon against the darkness closing in on their mother.

George had written and illustrated a full “battle plan” complete with diagrams: how he would bring her tea every morning, read her his history essays out loud because “you said they make you laugh,” and personally guard the door so no one tired her out.

Charlotte, with her perfect handwriting, filled ten pages with “Reasons You Are the Best Mummy in the World,” each accompanied by a pressed flower from the Windsor gardens and a tiny crown sticker. Page 7 simply read: “You taught me that princesses can be brave even when they’re scared. Now it’s our turn.”

Louis (who still mixes up his b’s and d’s) had dictated to his siblings entire pages in giant, wobbly capitals: “I WILL GIVE YOU ALL MY CUDDLES UNTIL YOU ARE 1000% BETTER. WINKS SAYS HE WILL SLEEP ON YOUR PILLOW AND BITE ANY BAD CELLS.” There was also a full-page drawing of Kate as a superhero wearing a cape made of corgi fur, punching a cartoon cancer cell into space.

The last page was written together in purple marker, the colour Kate always calls “brave colour”:

“Dear Mummy, We heard you have to fight the biggest dragon yet. We are small but we are loud and we are LOUDLY on your team. You once told us love is the strongest medicine in the world. So we made you this book full of it. Take one page every day until you’re bored of being brave and ready to be silly again. We love you bigger than the moon, the stars, and all the Lego in Denmark. See you on the other side of better. Your soldiers forever, George, Charlotte & Louis (xxx Winks)”

William found the book wrapped in Christmas paper (the only wrapping paper they could find in October) and placed gently on Kate’s pillow. Next to it was a single daisy chain long enough to stretch across the entire bed.

When Kate was shown the book two days later (still in hospital, still reeling from the new treatment plan), she reportedly held it to her chest and sobbed so hard the nurses thought something had gone wrong. Then she laughed, then sobbed again, then demanded it be read to her three times in a row.

King Charles, informed by a tear-streaked William, asked to see it privately. Palace staff say he locked himself in the Belgian Suite for nearly an hour. When he emerged, his eyes were red and he simply said: “Those children… they’ve just done what centuries of crowns never managed. They reminded us what actually matters.”

The book now travels with Kate everywhere (inside a protective plastic sleeve, because Louis keeps trying to add new drawings). Doctors say her pain scores have dropped noticeably on the days she reads a new page.

And the three little authors? They’ve instituted a new nightly ritual. Every evening at 7 p.m., wherever Kate is in the world, they FaceTime her, hold up that day’s page, and read it out loud together.

Because some medicines don’t come in bottles.

They come in crayon, glitter glue, and the unbreakable love of three children who decided that if their mum has to fight a dragon, she’ll do it with an army that never learned the meaning of surrender.