Kate Middleton has a mysterious 3-inch scar on her head -- here's what experts believe happened

For Kate Middleton -- or any other member of the British royal family, for that matter -- no detail goes unnoticed. From the tiniest jewelry details to the not-so-subtle hack she uses to keep her updos in place, being a high-profile royal like the Duchess of Cambridge means subjecting yourself to constant scrutiny from the public. 

And now, eagle-eyed royal fans have resurfaced yet another observation about the 37-year-old mother-of-three, and it's a detail that's (of course) been supplemented with its fair share of conspiracy theories. 

Although it's not as apparent in newer photos, Duchess Kate has a three-inch scar on the left side of her head. You can see it peek through in this photo from her first-ever solo engagement, a 2011 event at Clarence House. 

While the duchess has become skilled at concealing her scar under a hat or with an updo, many can't help but wonder where the scar originates from. 

Initially, beauty fans suspected that it was just a protrusion from hair extensions, but a spokesman quickly refuted that suspicion. "The scar is related to a childhood operation," said the source to E! News in 2011. Of course, the spokesman's broad response only ignited concern from many: was it serious? Details, please! 

Suspected a doctor to The Daily Mail at the time: "I really doubt it was any serious medical condition and I would say it is as a result of an arteriovenous malformation—a birthmark—being removed." It's "remarkable" that no one noticed it before the 2011 event given the size, said surgeon John Scurr to the publication.

Let's just go with that. And on that note, Kate's hairstylist definitely deserves a raise. Bravo!  

RELATED: See more of Kate before she was a royal

27 PHOTOS
Kate Middleton before she was a royal
See Gallery
Kate Middleton before she was a royal
An adorable Kate smiles at the camera, age five.
Kate skis in the Klosters with William and family.
A 3 year-old Kate wearing bright stripes.
ST ANDREWS, SCOTLAND - JUNE 23: New graduate Kate Middleton attends the graduation ceremony at St Andrews University to collect his 2:1 Master of Arts Degree in Geography in St Andrew's on June 23, 2005, St Andrews, Scotland. (Photo by Tim Graham/Getty Images)
LONDON - MAY 14: (EMBARGOED FOR PUBLICATION IN UK TABLOID NEWSPAPERS UNTIL 48 HOURS AFTER CREATE DATE AND TIME) Kate Middleton (C) and guests attend the book launch party of The Young Stalin: The Adventurous Early Life Of The Dictator 1878-1917 by Simon Sebag Montefiore, at Asprey May 14, 2007 in London, England. (Photo by Dave M. Benett/Getty Images)
Prince William's girlfriend Kate Middleton leaves the paddock enclosure on the first day of the Cheltenham Race Festival at Cheltenham Race course, in Gloucestershire 13 March 2007. (Photo credit should read CARL DE SOUZA/AFP/Getty Images)
ETON, UNITED KINGDOM - MARCH 18: Prince William kisses Kate Middleton, after playing the Field Game in an old boys match at Eton College on March 18, 2006 in Eton, England. (Photo by Indigo/Getty Images)
Kate Middleton, former girlfriend of Prince William and an unknown friend chat as they watch a performance at Wembley stadium in north London, 01 July 2007, as 60 000 revellers join Princes William and Harry for the six-hour long extravaganza in memory of their late mother Diana. Prince William, who turned 25 on June 21, predicted it would be 'an incredible night' of music after watching preparations being made yesterday for the event which is timed for what would have been his mother's 46th birthday. Police were on high alert as the huge concert got under way, a day after Britain raised its security threat level to maximum. (Photo credit should read LEON NEAL/AFP/Getty Images)
PANGBOURNE, UNITED KINGDOM - UNDATED: In this undated collect photo provided by St Andrew's School, Kate Middleton (front row, C) is pictured in a hockey team photo during her time as a pupil at St Andrew's School in Pangbourne, Berkshire, England (1986-1995). Catherine, Duchess of Cambridge re-visited her former school on November 30, 2012 to take part in a day of activities and festivities to mark the occasion of St Andrew's Day. The Duchess visited the Pre-Prep School for under-5s, unveiled a plaque to officially open a new artificial turf playing field and met members of the school's hockey team, which she played for during her time as a pupil at the school. She was also given a private tour of the school and watched the school's Progressive Games which are traditional games played indoors by teachers and students on St Andrew's Day. (Photo provided by St Andrew's School - WPA Pool/Getty Images)
Kate Middleton, girlfriend of Prince William, attends the second day of the Gatcombe Park Festival of British Eventing at Gatcombe Park near Tetbury, England. Anwar Hussein/allactiondigital.com *** Local Caption *** Zara Phillips
Kate Middleton, girlfriend of Prince William.
Kate Middleton, girlfriend of Prince William, during their graduation ceremony. William got a 2:1 in geography after four years studying for his Master of Arts.
Kate Middleton, girlfriend of Prince William, does some shopping when she attends the second day of the Gatcombe Park Festival of British Eventing at Gatcombe Park near Tetbury, England. Anwar Hussein/allactiondigital.com *** Local Caption *** Zara Phillips
Kate Middleton, girlfriend of Prince William, leaves St Cyriac's Church, Lacock, Wiltshire, following the wedding of Laura Parker Bowles and Harry Lopes.
Kate Middleton, the girlfriend of Prince William, watches from the side-lines as he plays polo for the Highgrove team at Cirencester Park Polo Club.
Prince William's girlfriend Kate Middleton smiles at Sandhurst, where graduates, including Prince William, marched in today's Sovereign's parade.
Prince William and his girlfriend Kate Middleton enjoy the rugby as England play Italy in the RBS Six Nations Championship at Twickenham.
Prince William and his girlfriend Kate Middleton enjoy the rugby as England play Italy in the RBS Six Nations Championship at Twickenham.
Kate Middleton, girlfriend of Prince William, at the races on the last day of Cheltenham Festival.
Kate Middleton, girlfriend of Prince William, at the races on the last day of Cheltenham Festival.
Kate Middleton (second right), former girlfriend of Prince William, walking the cross country course at the Mitsubishi Motors Badminton Horse Trials.
Kate Middleton, former girlfriend of Prince William, walking the cross country course at the Mitsubishi Motors Badminton Horse Trials.
Kate Middleton (centre), former girlfriend of Britain's Prince William (not pictured), during today's star-studded pop concert in memory of Diana, Princess of Wales.
Kate Middleton, girlfriend of Prince William, hosting Time to Reflect, an exhibition of limited edition photographs of celebrities by Alistair Morrison, at the Bluebird, London which Miss Middleton arranged to raise funds for UNICEF.
Prince William and his girlfriend Kate Middleton walk in RAF Cranwell, Lincolnshire after William received his RAF wings from his father the Prince of Wales.
Prince William (standing left) on his birthday with girlfriend Kate Middleton (standing right) watch the William De Broe Polo Test Match featuring England v New Zealand at the Beaufort Polo Club near Westonbirt. England won the match 6-4.
Prince William with his girlfriend Kate Middleton in the audience during the graduation ceremony at RAF Shawbury in Shropshire.
HIDE CAPTION
SHOW CAPTION
of
SEE ALL
BACK TO SLIDE

Read Full Story