On Monday, The Sun reported the 38-year-old royal “struggled to breathe” while he battled the novel virus back in April during the early days of the global pandemic. The U.K.-based outlet reported the Duke of Cambridge didn’t speak out about the illness to avoid alarming the public.
“Here in Britain, there is controversy over the fact that we now discovered that he had COVID-19 back at the beginning of the first spike and he concealed it,” royal author Robert Lacey told Fox News. “At the time, the prime minister had coronavirus, his father had coronavirus.”
Lacey, who serves as a historical consultant to the hit Netflix series “The Crown,” recently released a new book titled “Battle of Brothers: William and Harry - The Inside Story of a Family in Tumult,” which examines the relationship and alleged feud between Princess Diana’s two sons.
Lacey, who has been writing about the British royal family for 40 years and previously worked at the royal archives, spoke to numerous palace insiders for his latest release.
“[William] decided the world didn’t need him to be the third high-profiled coronavirus victim,” Lacey explained. “He followed all the rules. He did the quarantine, the self-isolating. He did Zoom, even while he was ill, and then got back to work.”
William reportedly tested positive only days after his father, Prince Charles, also tested positive for COVID-19 in late March.
Prime Minister Boris Johnson also contracted the virus around the same time. It is currently unclear if any other royals contracted the virus. It is believed William was treated by palace doctors and isolated in his Norfolk family home, Anmer Hall.
A source told the outlet that the Duke of Cambridge, who is second in line to the throne, "was hit pretty hard by the virus."
"At one stage he was struggling to breathe, so obviously everyone around him was pretty panicked," they added. "After seeing medics and testing positive -- which was obviously quite a shock given how fit and healthy he is -- William was determined it should be business as usual though.”
After April 9, the royal took a weeklong break from phone calls and engagements before virtually opening the Nightingale Hospital Birmingham on April 16.
“People have said this is not right for an heir to the throne to keep this sort of thing a secret,” said Lacey. “He should be open. He’s hiding things from us. I, myself, in this case, do not agree with that criticism. It’s not unconstitutional to choose to be ill in private. He doesn’t have to share his pains and tribulations with the rest of the world. Nothing improper was concealed. I think he was quite entitled to keep it private.”
Reps for the royal family did not immediately respond to Fox News’ request for comment.
According to The Sun, in the unlikely event that Queen Elizabeth II, 94, Charles, 71, and William were to all perish, George would technically be next in line to be the monarch. However, the Regency Acts notes that should such a tragedy occur before George's 18th birthday, a regent over 21 years old would rule in his place. Following George in the line of success are his two younger siblings, so his uncle Prince Harry would take on the role.
Even though Harry, 36, and his wife Meghan Markle stepped back as senior members of the royal family earlier this year, the Duke of Sussex is still in the line of succession. The next eligible heir is Prince Andrew, who also stepped back amid controversy surrounding his friendship with Jeffrey Epstein. The next in line would be the 60-year-old’s daughter Princess Beatrice, 32.
People magazine also pointed out that it’s not unusual for the palace to not announce any health scares. When Elizabeth underwent planned cataract surgery in 2018, the palace didn’t share the news until a month later.
William’s reported diagnosis came a few weeks after he joked about spreading coronavirus while touring Ireland in March with Middleton, 38.
The U.K. recently announced a second strict lockdown in the wake of rising cases of coronavirus.
Fox News’ Nate Day contributed to this report.