Queen Elizabeth II reportedly has sleepless nights due to the tragedy that keeps on haunting her in the past decades.

For years, the monarchy follows the line of succession to allow smooth and commendable transition once a monarch dies or abdicates. As of the writing, Prince Charles serves as the heir to the throne, waiting to take over Queen Elizabeth II soon. Following him on the list are Prince William, Prince George, Princess Charlotte, and Prince Louis.

The Sussexes - Prince Harry, Archie, and Lilibet - come thereafter.

However, concerns continued to rise after Prince William started flying himself and his kids in a helicopter. For what it's worth, the royal protocol has been banning two heirs from being on the same flight together. 

With that, Queen Elizabeth II is extremely worried about them, especially since she can still clearly recall a tragic event that happened decades ago.

Queen Elizabeth II Haunted By THIS Memory

A source recently told Express that the monarch still thinks of the helicopter accident in 1967 that killed the Captain of the Queen's Flight, Air Commodore John Blount, and three others.

Her Majesty was devastated at that time that she never boarded a helicopter until she needed to during her Silver Jubilee celebration in 1977 to travel to Northern Ireland. Per the insider, the accident "put her off completely," and she fears a similar incident might happen to the Duke of Cambridge and his family.

With her growing concerns, Queen Elizabeth II will reportedly have words with Prince William once he returns from Norfolk, where he celebrated Christmas with his family.

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The revelation came after Each Night released the result of the Google search data, showing that the "Prince Harry king" search increased by 769 percent in the UK on December 20 alone. This happened soon after Queen Elizabeth II urged Prince William to stop flying helicopters alongside his family - especially his children - due to succession fears.

"While all the Queen's family will be incredibly precious to her, Prince William and his three children represent a bright future for the monarchy, and she will want to ensure that they stay safe and well, ready to receive the Crown," a spokesperson for Each Night said.

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