Prince Harry shares sweet 'pinky promise' with 7-year-old girl at the WellChild Awards

The Duke and Duchess of Sussex stepped out Tuesday night in London to attend the WellChild Awards, a national organization that supports ill children and their families. Prince Harry has been a patron of the charity since 2007, but it was Meghan's first time attending the event.

The couple was welcomed by 7-year-old Matilda Booth, one of the winners of this year's awards, who has undergone more than 40 surgeries due to her Spina Bifida, or "split spine." The rare birth defect affects between 1,500 to 2,000 babies born in the United States every year.

Matilda, who is paralyzed from the waist down, handed Duchess Meghan a bouquet of flowers. According to reports, the Duchess of Sussex took one of the yellow flowers from the bouquet and handed it back to Matilda, telling her to store it in her "memory box."

PHOTOS: See more of the Duke and Duchess of Sussex at Tuesday's event:

Prince Harry then bent down to shake Matilda's hand and chat with the award recipient, asking her to promise to "never stop smiling." The two swore on it with a pinky promise.

"They were just so lovely," said Matilda's mom Sharon to the Daily Mail. "It was very exciting. Matilda had watched the royal wedding and was very nervous about meeting them but they completely put us at ease," she continued.

The couple also spent time with 4-year-old McKenzie Brackley, who was left paralyzed by a rare virus at age 2. Harry and Meghan were told that McKenzie was afraid of cameras, so they calmly turned the little boy away from the press. Prince Harry explained that they "didn't like cameras either."

"He’s never going to forget this, even though he’s only four," said his mom to the Daily Mail.

Learn more about the royals' work with WellChild in the video above.

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