King Charles, 74, and Queen Camilla, 75, arrived at the Coronation Concert on May 5 after all members of the Royal Family had taken their seats.
Kate Middleton, 41, made a conscious effort to curtsy to both the King and Queen, however, Prince William and Princess Eugenie, for example, only performed the gesture for Charles.
Prince George and Princess Charlotte notably followed their father’s example and did not appear to bow or curtsy to Queen Camilla.
According to royal protocol, Queen Camilla is more senior than the Prince of Wales, and would usually be received with a bow.
However, it is likely that William already saw Camilla that day and may have already bowed to the Queen Consort without the cameras filming their every move.
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Judi James, a professional body language expert, spoke exclusively to Express.co.uk to explain why Kate curtsied but the other royals seemingly did not.
She claimed: “This is a unique example of selective bowing, where William, Charlotte and George opt to not bow or curtsy to Camilla in keeping with protocol, but Kate drops a deep curtsy to both Charles and Camilla.
“It looks like an appeasement gesture after Camilla has been elevated to the role of Queen.”
According to the expert, the Princess of Wales’s gesture was “warm” to her step-mother-in-law.
Judi opined: “Kate engages Camilla in some eye contact and a warm smile before dropping into a curtsy that she might not have performed before the Coronation.
“There must have been a sense of awareness of Camilla’s new role and status and we can see the Duke of Gloucester dropping his head before Kate makes a similar gesture.
“Kate smiles at Camilla here before curtsying and it appears that she is still in the role of royal peace-maker here.”
Judi argued that the Prince of Wales may have felt some loyalty to the late Princess Diana at this moment and chose to follow his gut instinct.
She suggested: “Would William have felt comfortable bowing to the woman who took the place of his mother on the throne of the UK?
“He turns to look at his father but avoids looking at his stepmother.” The Princess of Wales, on the other hand, acted in a polar opposite manner to her husband.
The body language expert argued this was likely because Kate will one day be a Queen Consort and would want the same respect afforded to her.
Judi claimed: “Meanwhile, Kate looks keen to register an end to any sense of animosity or resentment with this one simple gesture of respect from a future Queen to the current one.”
