“Kate almost seems to ‘feel’ his stare and she responds to it quickly, turning her head to return the smile as the couple gave the world a very small glimpse into the strength of their feelings for one another.” 

She continued: “In the current clip we can see a similar side-by-side pose and, again, Kate sits looking lost in thought with her facial expression suggesting the rather moving Christmas song might be making her nostalgic or even tearful. 

“Yet again it is the intensity of William’s gaze that Kate seems to ‘feel’, and again her head snaps round to see it and to respond.” 

As for William, Judi said: “[His] compressed smile, with the lips, clamped together and some puckering at the corners and above the upper lip looks very similar to the smile he threw Kate on their wedding day.