Duchess Catherine and Prince William's code name used for royal engagements has been revealed by a royal expert.
Kate and William surprised schoolchildren at Casterton Primary Academy in Burnley whose parents are key workers with a video call.
One child showed the couple a painting of his mother, who worked for the NHS.
The duchess then told the young boy, 'You should be very proud of her, they're doing an amazing job, all the NHS workers.'
While William added, 'We just wanted to say a huge thank you to you guys and well done and keep it all going.'
After screenshots of the video call surfaced, royal expert Omid Scobie noticed the code name the royal couple used on video-calling app, Zoom.
What is Duchess Catherine and Prince William's screen name?
Speaking on ABC's HeirPod, Omid Scoobie said, 'Their screen name showed up in some of the screenshots.
'It was DOC meaning Duke and Duchess of Cambridge.'
He added, 'This was a chance to see William and Kate and how they are with the children.
'There were some really sweet moments.
'I think it was just a chance to see William and Kate at work and perhaps probably the up close and personal way we ever have.
'Usually the footage that's shared by TV cameras or photographers is from arms lengths and this is a firsthand account of what it is like to be on an engagement with them.
'I'm sure we will see a lot more of that over the days ahead.
'It was really sweet.'
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