Prince Harry didn't tell his father Charles he was writing an explosive new book about his life.
Charles only found out about the upcoming memoir from Palace officials when Page Six broke the story, it's been reported.
One source told Page Six that Prince Charles was "surprised" by the announcement.
"No one knew," another insider revealed. "There was chaos when the Page Six story came out."
Charles could well be concerned about the contents of the book, as Harry has spoken out against him in recent interviews. In May, Harry told podcast host Dax Shepard that his father had "passed down a cycle of genetic pain and suffering" to him.
Harry has spoken out against his father in recent interviews, and in May he told podcast host Dax Shepard that Charles, 72, "passed down a cycle" of "genetic pain and suffering" to him.
Harry will reportedly donate all the proceeds from the upcoming book to charity, despite his huge content deals with Spotify and Netflix.
The 36-year-old has secretly been writing the memoir about his life growing up as a royal, his relationship with Meghan Markle and becoming a father, reports The Sun.
It's not clear how much the advance for the book was, but Harry will be donating all the profits to charity, according to publisher Penguin Random House.
Last year, Harry and Meghan signed a multi-million dollar deal with Netflix. They agreed to a multi-year deal to create nature shows, children's programmes and documentaries for the platform.
Prince Harry claimed in the couple's explosive Oprah Winfrey interview that they accepted the projects as they had been financially cut off by the royal family after announcing their Megxit plans.
"We didn't have a plan," he told the talk show host.
"That was suggested by somebody else by the point of where my family literally cut me off financially, and I had to afford security for us."
He added: "I've got what my mum left me, and without that, we would not have been able to do this."
Harry said of his new book: "I'm writing this not as the prince I was born but as the man I have become.
"I've worn many hats over the years, both literally and figuratively, and my hope that in telling my story - the highs and lows, the mistakes, the lessons learned - I can help show that no matter where we come from, we have more in common than we think.
"I'm deeply grateful for the opportunity to share what I've learned over the course of my life so far and excited for people to read a firsthand account of my life that's accurate and wholly truthful."
He's reportedly been writing the book for nearly a year. The manuscript was originally due to be sent to publishers next month, but this has been pushed out until October.
A statement from Penguin Random House said: "In an intimate and heartfelt memoir from one of the most fascinating and influential global figures of our time, Prince Harry will share, for the very first time, the definitive account of the experiences, adventures, losses, and life lessons that have helped shape him."
The book promises to cover Harry's life from his childhood to the present day, including his military duty in Afghanistan and his transformation into husband and father in a "captivating personal portrait".