Ms Bolton told Express.co.uk: “In the image of Kate and William walking they are both striding confidently.
“Kate is full of confidence but a little nervous as her left hand is in front of her body as if she wants people to stay a little further back from her.
“William has seen someone that he knows by the look of friendly recognition.
“At the same time, he is unsure what is about to happen as something is different than what he was expecting.
“It is not something huge as his expression shows that he will be able to cope with it.”