King Charles and Queen Camilla's happy marriage is down to this one rule and it's not what we expected

King Charles and Queen Camilla's happy marriage is not what one might expect as it's definitely leaning on the separate side of things as opposed to promoting togetherness. Seemingly the rule in question, sleeping in separate beds, isn't uniquely theirs and in fact - it's a pretty royal tradition!

• King Charles and Queen Camilla's happy marriage is aided by sleeping in separate bedrooms.
• This is reportedly for numerous reasons including tradition and owing to an ailment that affects the King.
• In other royal news, Throwback Princess Anne interview reveals surprisingly humble backup plan if she wasn’t a royal.

King Charles and Queen Camilla's happy marriage is reportedly sleeping in separate bedrooms. 

Per the Mirror, "it is usually customary for married members of the Royal Family to have separate bathrooms, it has been reported. For example, Prince William and his wife Kate slept separately while living in Kensington Palace, while Queen Elizabeth and Prince Philip also slept apart."

This tradition, according to one royal insider, is because members of the British upper class, “always have separate bedrooms."

Writer Sally Bedell Smith spoke to Lady Pamela Hicks, a cousin of Prince Philip, in her biography of Queen Elizabeth II, Elizabeth the Queen: The Life of a Modern Monarch. 

Lady Pamela explained, “In England, the upper class always have had separate bedrooms. You don’t want to be bothered with snoring or someone flinging a leg around. Then when you are feeling cozy you share your room sometimes. It is lovely to be able to choose.”

According to the Express - the royal couple have another reason for having separate bedrooms and it's all down to King Charles's health.

"Charles and Camilla retire to different rooms in the evening, it is apparently because of the King’s health," explained the publication. "Charles has well-known back pain, and sleeping alone is believed to help ease back pain."

This chronic pain was also discussed in Prince Harry's memoir Spare, where King Charles's wild morning routine was revealed. The Prince claimed that his father used to engage in a series of headstands each morning on advice from his physiotherapist to help aid his back pain. The pain, seemingly, is owing to old polo injuries that have wreaked havoc on the royal's back.

“He performed them daily, in a pair of boxers," revealed the Prince, propped against a door or hanging from a bar like a skilled acrobat.” 

It's unclear whether the tradition of sleeping in separate rooms continues in the younger generations. However, according to the floorplans of Prince William and Princess Kate's Kensington Palace apartment, it looks like they share a bedroom.

The Express reported that the 'main bedroom' is on the ground floor of their large living quarters, with the servants living upstairs - which is in itself an unusual and untraditional living arrangement for royals.