Just a day after announcing their new YouTube channel, the Duke and Duchess of Cambridge have released their first full video.

Thursday’s video, titled "Shielding Mila-Hold Still," reveals a recorded conversation Kate Middleton had with 4-year-old Mila Sneddon and her mom Lynda during autumn 2020. At the time, the duchess was having conversations with finalists from the National Portrait Gallery’s "Hold Still" photography exhibition, which chronicled people’s lives in the U.K. during lockdown.

According to the video, the 39-year-old mother of three wanted to speak with some of the finalists to find out more about the stories behind their photos. A week prior to lockdown due to the coronavirus pandemic, Sneddon’s family had to isolate in different households to protect the child, who was four months into chemotherapy for acute lymphoblastic leukemia.  

Sneddon stayed at home with her mom while her father Scott and older sister Jodi stayed elsewhere to minimize the little girl’s risk of infection. The matriarch’s photo submitted to the exhibition showed Sneddon kissing the window as her father stood outside smiling.  

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Sneddon, who answered the phone, said, "Good morning, Your Royal Highness!"  

"Good morning," Middleton chuckled. "My goodness me, you’re so polite, Mila!"

Sneddon later asked, "Do you have a costume?" The duchess replied, "I’m not wearing a princess costume right now, I’m afraid Mila."

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When Sneddon told Middleton her favorite color is pink, the royal said, "OK well I have to make sure I go and try and find myself a pink dress. Hopefully, when, one day, hopefully, Mila, we’ll get to meet and then I’ll remember to wear my pink dress for you."  

Sneddon cheered as Middleton laughed and said, "Would that be nice?"

The child also told Middleton, "I know all your kid’s names!" and correctly listed Princess Charlotte, Prince George and Prince Louis. Middleton said, "Louis has got so big now. He’s very quick running around, and he’s on his little scooter as well. He’s very quick. I can’t keep up with him."

On Wednesday, the Duke and Duchess of Cambridge shared a promo video for their YouTube channel.

Previously, the couple revealed a sweet, 40-second video of the parents playing outdoors with their three children. That video was shared as a special thanks to fans who congratulated them on their 10th wedding anniversary.

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"Thank you to everyone for the kind messages on our wedding anniversary," said their online note. "We are enormously grateful for the 10 years of support we have received in our lives as a family."