Kate Middleton reportedly made a swift head-turning gesture from Queen Camilla during the historical Trooping the Colour event on Saturday according to a body language expert, as royals gathered to mark the monarch's 74th birthday.
On November 14 each year, King Charles marks his birthday privately, but each year in June he marks his "official" birthday with the military spectacle where the most prestigious regiments in the British Army honour the monarch by parading for the special day.
Charles rode in the parade on a horse called Noble after riding from Buckingham Palace to Horse Guards Parade, he then lined up alongside Prince William, Princess Anne and Prince Edward as well as Princess Kate and Queen Camilla.
The 74-year-old monarch appeared to struggle as the horse became excitable, and according to body language expert Judi James, Camilla was on the sidelines to try and provide support but the Princess of Wales Kate Middleton stayed clear.
She explained to the Mirror: "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.
"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.
"Kate took one glance at the conversation and turned her head away, clearly not wanting to get involved."
Elsewhere, Judi also noted a change with William and Kate's cheeky son Prince Louis but said he still remained his excitable self thanks to his mum.
She explained: "With Louis now dressed exactly like George, it is obvious that his behaviour is also getting more grown-up and less playful but there were several signs that, with the encouragement of Kate, he is still enjoying his royal events and getting excited by everything going on around him.
"He strode out first when he and his siblings walked from their carriage on the parade ground and when he was in the carriage he got a beam from Kate as he mimed drumming while the band played.
"On the balcony, he turned to chat to his parents but his enthusiasm for the Red Arrows was obvious from his impatience signal as he waited for them to arrive, rolling his hands into fists and punching them together.
"With this slimmed-down monarchy, there was more of a less formal, family feel to the balcony group. Camilla was chatting to Charles as they walked out and Charlotte had to squeeze out behind her grandfather, followed by an equally squeezing-through Kate.
"Sophie and Edward chatted to Charles and Camilla, with Sophie making her husband laugh as she mimed how close two of the planes had flown and Charles chatted frequently to William, with the pair showing signs of a new, more easy-going bonding."
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