Kate Middleton reflected on how quickly her children are growing up.

On Thursday, Sept. 4, Princess Kate and Prince William paid a visit to the Natural History Museum in London to tour the institution’s newly renovated gardens.

The Prince and Princess of Wales, both 43, stopped to chat with some locals outside the museum, including one who asked after the couple’s children, Prince George, 12, Princess Charlotte, 10, and Prince Louis, 7.

“They’re getting big now,” Kate said, gesturing with her hand that they were almost as tall as her, as seen in a video shared on TikTok.

She added, “George is already in my shoes,” seeming to indicate that they wore the same size.

When the supporter shared that they were part of the crowd of well-wishers outside the Lindo Wing at St. Mary’s Hospital when Kate gave birth to all three children, the royal shared her thanks.

“It only feels like yesterday,” she reflected.

According to the supporter, Princess Kate sent breakfast to the gathered crowd, for which they were very grateful.

“Good, you got it,” she said. “It was the least I could do.”

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The Princess of Wales paid special tribute to her children during the museum visit, wearing a delicate gold necklace featuring charms of their initials in birth order. The piece is a sentimental favorite of Kate’s and has been in her royal rotation since 2021.

Prince William and Princess Kate’s royal outing came just a day after the children’s return to school. This year will be the last that George, Charlotte and Louis will all be enrolled together at Lambrook School, as Prince George will age out of the coeducational prep school next summer when he turns 13.

While the family hasn’t yet made an official announcement about where he will attend next, Prince William’s alma mater, Eton College, has been earmarked as the front-runner.