George, seven, and Charlotte, five, appear to be sitting back-to-back with their heads turned to the camera in the never-before-seen photo. Both are wearing khaki-coloured tops, although it's not clear when the photo was taken.
WATCH: Kate gives sneak peek of new photo of Prince George and Princess Charlotte
Also spotted on the console table behind Kate were family photos that royal fans are already familiar with, including George and Charlotte on the Princess' first day of school at Thomas' Battersea. A central image is of Kate cooing over her youngest child, Prince Louis, at her garden at the RHS Chelsea Flower Show in 2019.
Another framed photo is from Princess Charlotte's christening, while a solo portrait shows Prince William during a trip to Africa in September 2018.
A new photo of George and Charlotte was spotted in the background
The Cambridges have been using the Queen's house at Sandringham as a second property to take video calls from. They have also recorded some of their working calls from their country home, Anmer Hall. But one thing that always stays the same is William and Kate's desire to have a sweet photo display of family pictures behind them.
During Thursday's call, the Duchess spoke to staff at Ribbon Academy in Murton. Since 2002, the school has worked with the children's mental health charity Place2Be, of which Kate is patron, and she heard how it has been supporting pupils and staff throughout the pandemic.
Kate praised teachers and educators for being a "lifeline" to families
The royal mum was full of praise for educators as she said: "I think everyone can recognise that schools are doing an amazing job. As parents as well, you really recognise what a vital role you do play for us on a day-to-day basis. Having remote learning going on as well, [it must] be hugely challenging to juggle both for a school."
Kate also told teacher Louise Tweedie: "[I'm] so passionate about all the work that teachers up and down the country are doing. You are doing the most amazing job. You are a lifeline to so many families out there. I know it takes an awful lot of effort, energy, and patience. Thank you for the hard work you do on a day-to-day basis for the children that you look after."
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