The body language expert exclusively told the Mirror: “While William and Edward sat bolt upright on their very calm horses, with right arms rigid at their sides, Charles frequently needed two hands on the reins and a series of pats that increased in intensity as his horse needed steering and correcting throughout the ride to the parade ground.
“The King seemed to be complaining again to Camilla once he arrived beside the rostrum where she was standing, meaning instead of offering a smile of pride and support her body language suggested she was giving a rather stern-looking pep-talk than involved frowning and some firm-looking head baton nods.”
She added: “Trooping the Colour might have been slightly marred by the rather frisky horse that Charles seemed to be struggling with and which meant he rarely achieved the same kind of formal mounted pose that his son and siblings achieved riding behind him to the parade ground.”
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The King rode a horse named Noble during the parade. The King riding horseback also held some significance as it was the first time a monarch had done so since 1986.
The late Queen was the last monarch to have rode horseback at Trooping the Colour.
After 1986, Queen Elizabeth II opted to travel in a carriage for future appearances at the event as her usual horse retired.
Speaking of the pep talk between the royal couple, the royal expert noticed that Kate was present but chose to stay out of it.
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She said: “Kate took one glance at the conversation and turned her head away, clearly not wanting to get involved.”
Trooping the Colour is an annual event which marks the monarch’s official birthday – with this year’s celebrating the first of a King in 70 years.
The Royal Family came together for a morning of pomp and pageantry, with spectators lining the Mall to celebrate the historic occasion.