Young Prince Harry “told William he could do whatever he wanted,” says the royal author

Royal author Robert Jobson says Prince Harry’s mischievous nature was always encouraged by his mother, Princess Diana, and while he felt overshadowed by his brother, he knew he could get away with far more

Prince Harry always reveled in the freedom he enjoyed as a child — something he knew brother William would never have, claims a royal author.

Robert Jobson said the “wicked” little king is “completely out of control at times” and told his older sibling and second in line to the throne he could “do whatever I want”.

The now Duke of Sussex, 37, often felt overshadowed by the attention William received, including deference from royal staff at a young age.

He would also be invited to visit the Queen Mother alone and without his younger sibling.

The author and journalist said that while Harry never directly expressed his grudges in public, it did create tension between the two.

But this came out on shows of cheeky rebellion, which her mother, Princess Diana, found “hilarious”.

At one point, the three were driven to Prince Charles’ home in Highgrove, Gloucestershire, along with Royal Protection Officer Ken Wharfe.

Harry and William, just six and eight, were arguing in the back seat as the younger brother said: “You’re going to be king. I won’t – so I can do what I want!”

Jobson writes in his new book, William At 40: The Making Of A Modern Monarch, excerpts of which will be published in the daily mailDiana and Wharfe said they were “a little shocked,” the constable later told him.

The author said: “Certainly Harry seemed to be reveling in the freedom he knew William would never have. He was far more mischievous – and completely out of control at times.”

And while William was “also capable of wild behavior,” he could become “irritated” by how far Harry would go and often come across as a “babber-jack” to his brother.

Diana, on the other hand, was keen to embrace such a rebellion.

Once, when Harry got into trouble at school for pulling the music teacher’s trousers on while she was playing the piano, “she burst into a fit of giggles” when she had to go in to discuss his behavior.

“The truth is that the Princess actively encouraged Harry’s mischievous nature, which in some ways resembled her own,” Jobson said.

When they arrived at William’s in Highgrove after Harry’s outburst, Diana encouraged them to stage a kart race and destroy Charles’s immaculate grounds.

Her father was away at the time.

Jobson said Diana “believed in letting her boys run wild and free” and they would “roam around the Highgrove compound like a bunch of rascals.”

Charles and Diana often left the two boys in the care of nannies and guards in charge of discipline, with Harry once angering one of the former by telling her to lose weight.

Wharfe recalled how they both would regularly team up to punch him in the head and groin during playful wrestling matches.

However, he wasn’t as forgiving as others in his role.

He recalled an outgoing officer telling his successor “good luck” and that if William and Harry had been raised on welfare, “they would have been taken into care by now.”