Prince William and Kate Middleton got their fans worried when they released a never-before-seen photo to mark their 13th wedding anniversary.

The Prince and Princess of Wales released a black-and-white photo for their wedding anniversary on Monday. Prince William and Middleton tied the knot on April 29, 2011, at Westminster Abbey in London, England. The couple tagged Millie Pilkington, who captured the stunning shot.

However, several royal fans expressed concern at the first sight of the picture. According to them, they were scared because they thought something tragic happened, especially since Middleton announced her cancer diagnosis last month.

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"I have to admit I got scared for a moment, please don't do that :( Hope both of you enjoy this anniversary," a concerned fan commented.

Another added, "I was scared to see [a] monochrome photo. I wish you all the best in your life forever."

"Black and white photo? This scares me!" a third person remarked.

Some said they "almost faint[ed]" when they saw the picture. Another said they "almost [had] a heart attack."

Many also advised the others to chill because it was a beautiful photograph, and black and white photos are completely normal.

"Y'all need to chill out. B&W photography is completely normal and has no underlying meaning. [face with tears of joy emoji] ridiculous," one commenter wrote.

Another opined, "So many strange comments on here. So many weird people walking amongst us."

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Prince William and Kate Middleton's Royal Wedding
Their Royal Highnesses Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge wave on the balcony at Buckingham Palace during the Royal Wedding of Prince William to Catherine Middleton on April 29, 2011 in London, England.
(Photo : John Stillwell-WPA Pool/Getty Images)

"Is it against the law or something for a couple to post a B&W photo of their wedding? I've seen it many times, it's a good aesthetic. I don't understand the hoopla about this one," a different royal fan wrote.

"On that note, Happy Anniversary to William and Catherine of Wales. To many, many more years of happiness, good health and success. Cheers!"

Amar Guillen, a photographer who creates fine art prints of nature in black and white, acknowledged that black and white photos are transcribed as negative feelings. Many relate them to disasters and sad emotions. He noted that black and white is a reflection of sad emotions. For him, it could also be "synonymous with beauty and dreams" for landscape and wildlife photography.

Middleton disappeared from the public eye for months after the Palace announced that she had planned abdominal surgery in January. Several fans were wondering how she was doing, and in March, the Princess of Wales revealed that she had cancer.


Prince William and Kate Middleton's Royal Wedding
Their Royal Highnesses Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge kiss on the balcony at Buckingham Palace on April 29, 2011 in London, England.
(Photo : Peter Macdiarmid/Getty Images)

"At the time, it was thought that my condition was noncancerous," she said in a video shared on their official account on Instagram and X, formerly Twitter. "The surgery was successful. However, tests after the operation found cancer had been present."

"As you can imagine, this has taken time. It has taken me time to recover from major surgery in order to start my treatment. But, most importantly, it has taken us time to explain everything to George, Charlotte and Louis in a way that is appropriate for them, and to reassure them that I am going to be OK."

Middleton is currently focused on making a "full recovery." She has asked for "time, space and privacy" while she continues her treatment.