Inbaal discussed Charlotte and Louis’s first appearance as they walked behind their parents, the Prince and Princess of Wales into the Abbey.
She said: “Charlotte and Louis holding hands as they enter the Abbey could be interpreted as the older girl leading the younger boy and taking responsibility for him as an older sibling.
“However, their connection seems more affectionate than controlling.
“It is the way they hold hands, which is actually very equal. Both their hands close softly around one another’s, with no tension, and this shows that they’re both gaining comfort from feeling direct physical contact with someone loved and familiar.
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“Louis’s other hand is held in a light fist, which shows a small amount of apprehension, as the surroundings are a little overwhelming to him perhaps, but it’s not a tight fist, which is what we’d see if he were nervous.
“Both children are looking around, not at each other. Their physical touch allows them to explore independently, without the need for constant eye contact.”
During the ceremony, the two children interacted with one another, and the body language expert described their interactions as “loving and trusting”.
“Charlotte leans to listen properly to her brother, shortening the space between them, which shows that her caring nature is far beyond her eight years, and Louis talks to her while looking at her face, showing that he trusts her,” she added.
“They both appear to feel safe, and their movements are soft and confident, not remotely jumpy or insecure.”
At several points, however, it seems the ceremony was a little long for young Louis, who was spotted yawning and looking around, pointing to interesting things for Charlotte to look at.
Inbaal said: “Both Charlotte and Louis [looked] bored during the ceremony. She has learned not to yawn in public, but her eyes wander, her thoughts are far away, she’s chewing her lip, deep in thought.
“Louis, at the same time, is trying to find something interesting, looking around him and yawning.
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“She pulls her lips into a smile, teeth showing, in that way that kids are taught to ‘cheese’ at the camera, but her eyes aren’t smiling, they’re not pulled up as during a natural, happy smile
“Louis is still on best behaviour, going through the motions – his hand is up, he is waving, doing what’s been asked of him.
“Pulling a smile is a learned behaviour, which Louis hasn’t adopted yet – and at five years of age, that’s to be expected. His funny faces are just a way for him to break the boredom,” Inbaal suggested.