Prince Harry is paying the price for writing his tell-all book Spare as he prepares to celebrate his 40th birthday, a prominent royal biographer has claimed, with polling in Britain still ranking him as one of the most unpopular members of the royal family.

Harry will turn 40 on September 15, and is expected to mark the day privately with wife Meghan Markle and their two children, Prince Archie and Princess Lilibet, at their home in Montecito, California.

According to recent polling by YouGov in the U.K., Harry is the third most unpopular royal with a net approval rating of -30. He is ahead of Meghan, whose net approval rating comes in at -40, and Prince Andrew—who is the most unpopular royal at -82.

At its peak, Harry had a net approval rating of +70 in November 2017, according to YouGov, hitting a record low on the day of Spare's publication in January 2023 at -44.

Prince Harry photographed in London in May 2024; inset, cover art for his book "Spare" published in 2023. Polls showed a slump in the prince's popularity in the weeks and months after the memoir came... Prince Harry photographed in London in May 2024; inset, cover art for his book "Spare" published in 2023. Polls showed a slump in the prince's popularity in the weeks and months after the memoir came out. Max Mumby/Indigo/Getty Images/RAMONA ROSALES/PENGUIN RANDOM HOUSE

Discussing on a new episode of The Sun's Royal Exclusive web show why Harry may be viewed so negatively, royal biographer Ingrid Seward—author of the 2003 book William & Harry—said that the prince's relationships with family members play a contributing role.

"I think what people really dislike that is he dissed his family," she said.

"I think the book Spare might have earned him millions, but gosh, he's paid for it. He's paying for it still."

Harry faced criticism after his memoir's publication for a number of critical assessments of family members including King Charles, Prince William and Queen Camilla.

In response to the claim these may have been hurtful, the prince told Anderson Cooper at the time: "None of anything I've written, anything that I've included is ever intended to hurt my family."

A paperback edition of Spare is set to be released worldwide in October.

Seward suggested that it wasn't just Harry's approach to his family in his memoir that may not appeal to the public, but also his apparent distancing from Meghan's family.

"I think especially amongst...the Americans that I know, they hate the idea that he dissed his family," she said. "He doesn't speak to his family, doesn't speak to his brother, has never met Meghan's father. I mean, it is very strange. Is Meghan ashamed of her father? Why hasn't Harry met him?"

This reference to Meghan's father, Thomas Markle, comes after he and the duchess had a public separation of ways around the time of the royal wedding in 2018.

Thomas Markle had been due to walk his daughter down the aisle at St George's Chapel, but after suffering public embarrassment linked to a collaboration with a member of the paparazzi he also experienced a serious health scare. In his absence, Meghan asked King Charles (when he was still Prince of Wales) to walk her down the aisle.

Since the wedding, Thomas Markle has publicly opined that his daughter is not in contact with him and that he has never met her husband or his two grandchildren. He has regularly criticized Meghan in TV and media appearances.

Princess Kate, Prince William, Prince Harry and Meghan Markle photographed in Windsor, September 2022. Harry listed a number of family grievances in his memoir "Spare." Princess Kate, Prince William, Prince Harry and Meghan Markle photographed in Windsor, September 2022. Harry listed a number of family grievances in his memoir "Spare." CHRIS JACKSON/POOL/AFP via Getty Images

Seward said that, from a public viewpoint, Meghan and Harry's relationships with family members contrasts with other royals.

"It's this sort of distancing from family, people find that very alienating," she said. "It's quite the opposite to what William and Kate were showing in their most recent video."

This refers to the three-minute video released by Kensington Palace on September 9, in which Princess Kate gave an update on her health, revealing that she had completed her chemotherapy treatment and was focused on staying "cancer free."

The video included intimate clips of the princess with Prince William and their children Prince George, Princess Charlotte and Prince Louis, as well as footage including Kate's parents, Carole and Michael Middleton.

Newsweek approached representatives of Prince Harry via email for comment.

Harry has reflected publicly on his milestone 40th birthday and what it means to him.

"I was anxious about 30, I'm excited about 40," he told the BBC via a statement on Friday. "Whatever the age, my mission is to continue showing up and doing good in the world."

James Crawford-Smith is Newsweek's royal reporter, based in London. You can find him on X (formerly Twitter) at @jrcrawfordsmith and read his stories on Newsweek's The Royals Facebook page.

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