The American actress was observed crossing her legs, which is considered a royal no-no.
Meghan Markle may have committed a royal faux pas as she and other members of the royal family marked the 100th anniversary of the Royal Air Force Tuesday.
Markle made what some observers are calling a royal faux pas as she crossed her legs during the ceremony. Protocol calls for her to slant her legs, like sister-in-law Kate Middleton was seen doing.
"Most royal ladies choose to sit with what they have nicknamed 'the Duchess Slant,'" royal expert Victoria Arbiter told Inside Edition. "When sitting down, it looks elegant, it looks classy, but more importantly it is to prevent photographers from getting inappropriate photographs."
The Duchess Slant involves sitting with knees touching and positioned off to the side.
Markle wore a custom-made Dior dress with a boat neck.
She held Prince Harry's arm as they arrived at Westminster Abbey for a special service honoring the Royal Air Force (RAF).
"Each time she steps out, you can see that there is a little bit more of a buzz in her step," Arbiter said. "You don’t sense at all that she is nervous."
She sat in the second row during the ceremony and strutted like she was on the Hollywood red carpet as she exited the cathedral.
Kate Middleton wore an Alexander McQueen dress to the event.
There was applause as the whole royal family converged on the balcony at Buckingham Palace. Markle stood in the center of the group alongside Queen Elizabeth.
They then watched the stunning flyover in the London sky, during which some jets trailed red, white and blue smoke.
The little royals, Charlotte and George, stole the show as they had a playful time watching all the action from inside the palace with their nanny.
Charlotte gave off a smart salute and at one point, she stuck out her tongue.
Tuesday's event was the second royal occasion in as many days. On Monday, the family celebrated the christening of Prince Louis.
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