Queen Elizabeth II reportedly keeps a secret diary, and only Prince Philip is allowed to read through its pages.

According to The Sun, Her Majesty even asks her royal staff to destroy the blotting paper used to absorb the ink every day to make sure that what she writes will be kept private.

The Queen usually writes about family news, her views on the people she has met, and other things since she was 15 years old. The monarch usually writes in her secret diary at night, and no one is allowed to disturb her during this time.

“The diary is taken with her wherever she is staying whether it be Windsor or Sandringham or Balmoral and is kept in a black leather case – a smaller version of one of the red despatch boxes containing government papers. But, there are only two keys – the spare one is kept strictly as an emergency back-up by her private secretary,” the source said.

Since the Queen was 15 years old, her secret diaries have never gone missing. This is because they are probably deemed almost as valuable as the monarch’s Crown Jewels. And if a footman, for example, loses the Queen’s diary, he might end up in the tower.

Meanwhile, the insider wasn’t the only person to ever talk about the Queen’s diaries. Sir Michael Palin, 76, also heard Her Majesty talk about her journal after he was chosen to sit next to her at dinner.

“We were talking about diaries after I had mentioned that I kept a knightly journal of where I’d been and the people I encountered, she said she did too, the difference being that while mine may have been for publication, hers was definitely not. She commented that she found it quite difficult because it always made her a bit woozy and said, ‘I usually manage to write for about 15 minutes before my head goes bump,’ and then she did an imitation of her head hitting the table as if she had fallen asleep,” he said.

Queen Elizabeth II
Queen Elizabeth II is seen at the Chichester Theatre while visiting West Sussex on Nov. 30, 2017, in Chichester, United Kingdom. Getty Images/Stuart C. Wilson