Kate Middleton Promises to Wear Pink Dress to Meet Girl with Leukemia: Listen to Their Sweet Call

The Duke and Duchess of Cambridge/Youtube Kate Middleton

Kate Middleton promised to wear a special outfit to meet a very special young girl.

Over the past year, Kate has spoken to many of the 100 finalists who shared their experiences of life during COVID-19 lockdown in the U.K. by submitting an image to the royal's Hold Still photography project. In honor of the publication of Hold Still: A Portrait of Our Nation in 2020 on Friday, Kensington Palace shared one of those phone calls — on Kate and Prince William's new YouTube channel! — on Thursday.

In August, Kate spoke to 4-year-old Mila about her photo, called "Shielding Mila," which showed the little girl waving to her dad from the other side of a window. Mila and her mother, Lynda, had to isolate away from Mila's father, Scott, and big sister, Jodi, to protect Mila while she was receiving chemotherapy for acute lymphoblastic leukemia.

Mila greeted Kate on the phone by saying, "Good morning, Your Royal Highness."

Kate responded with a laugh, "Good morning. My goodness me, you're so polite, Mila!"

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In addition to speaking about the photograph, Mila had a big question to ask the Duchess of Cambridge: "Do you have a costume?"

"I'm not wearing a princess costume right now, I'm afraid, Mila," Kate said.

After learning that Mila liked to play dress-up and that her favorite color was pink, Kate made her a promise: "I have to make sure I go and try to 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."

"Yay!" an excited Mila exclaimed.

"Would that be nice?" Kate said.

Later in the call, Mila told Kate: "I know all your kids' names."

Kate replied, "Do you? What are their names, can you remember?"

"Yes," Mila said, before rattling off Kate's three children's names: Charlotte, George and Louis.

"Yay," Kate exclaimed, adding, "Louis has gotten 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!"

The Duchess of Cambridge Prince Louis

Kate, 39, also spoke to Mila and Lynda about the photograph, which showed Mila looking at her father from inside a window. She learned that the family is now reunited and living together again.

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It was actually Lynda's mother who encouraged her to submit the photo.

"I'm very grateful," Kate said. "And also for sharing such a personal time. You know, it'll be an image that is part of a national archive, and you know, it tells a story of this particular time and a very personal story too, so thank you so much for sharing it."

More conversations between Kate and Hold Still participants are set to be released in coming weeks.

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Launched by the Duchess of Cambridge in May, Hold Still invited people of all ages to send in a portrait that they had taken during lockdown in an effort to capture the story of the people at this unique and challenging time.

"We've all been struck by some of the incredible images we've seen which have given us an insight into the experiences and stories of people across the country," Kate said in a statement at the time. "Some desperately sad images showing the human tragedy of this pandemic and other uplifting pictures showing people coming together to support those more vulnerable."