The video, shot by filmmaker Will Warr, showed the family playing by the beach and toasting marshmallows.
What did a body language expert make of it?
Body language expert Judi James told Express.co.uk: “This very sweet and also very smart video will create a lump in the throat of royals fans and might even make the cynics a little bit teary too.
“It’s smart because it shows us such a generous glimpse of family life chez Cambridges but without invading their own privacy or presenting the kind of stilted, awkward look of previous royal films shot over the years.”
The family manages to look so natural, the expert claimed, despite being filmed.
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