Prince William and Kate Middleton's all three children stole their sweet mum's Christmas carol concert with their stunning gestures on Friday.
Prince George, Princess Charlotte and Prince Louis - who walked into the Abbey - paused for a moment to post Christmas cards, in a special postbox, containing messages for children who might be struggling this Christmas, something open to all youngsters attending.
And looking at the footage of this, body language expert Judi James told The Mirror, the family of five have now turned into a "sweet, well-oiled machine".
The expert went on explaining: "It looks obvious from the way they all seem to know exactly where to walk and with whom. All three children trot off to the pillar box to post cards with little prompting from their parents and it is interesting to the point of amazing that playful Louis now seems to have found a place as the most well-trained-looking sibling in the group."
Reading Prince George's body language, Judi claims: "George now seems to have grown out of the 'child' stage and walks in the middle with the adults, looking like a mini-me of his father."
Princess Charlotte, according to the expert, showed her "hero-worship" for her dad William with a sweet yet telling gesture at the event.
Judi explained: "Even though she walks with her mother she throws a quick glance back at her father. William is doing his usual auto-contact checking gesture, placing one hand over his jacket in a partial barrier ritual. Charlotte picks up on this and mirrors William, performing an identical gesture as they walk into the Abbey.
"It's always seen as George who is the one who copies and mirrors his father, while Charlotte has copied Kate in the past but this one simple but twinned mimicry gesture suggests that Charlotte hero-worships both her mum and her dad and has strong feelings of empathy for William in particular."
Princess Kate, who hosted her annual Christmas carol concert at Westminster Abbey with husband Prince William and children Prince George, Princess Charlotte and Prince Louis on Friday, was also looking out of this world in all white ensemble.
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