Kate, 41, highlighted the work of portage practitioners during her visit, a home-visiting educational service for preschool children and their families.
The Princess got really involved in the session and was pictured tickling the children's tummies and throwing tinsel and shredded paper around.
Take a look at her sweet engagement in the clip below…
The heartwarming photographs have since prompted a flurry of comments on the Prince and Princess of Wales's social media accounts.
"Wonderful to see this important issue being highlighted. Great job!!!" one wrote.
"As an early years teacher, I can't be thankful enough for everything YRH [Your Royal Highness] is doing for our little ones!!" another said.
"Thank you for all you are doing to highlight and support this important work with early years," a third commented.
Naomi Nice, a portage practitioner who was at Kate's engagement, told HELLO! that awareness of portage services is "so important".
"If you just talk to the general public, people won't know who we are," she said. "No one will know who we are unless you know somebody who's had that service. And actually, when you talk to the parents who have received Portage, they talk about that lifeline.
"We're someone who's coming in from really early days, a lot of the time we get to know the family on a really personal basis, we're that port of call for them. So to highlight that awareness to the country of what it is that we're doing is vital to keep our services going at a time where services are being cut. And so when parents feel that we're their lifeline, that lifeline needs to stay."
Meanwhile, Janet Rickman, Chair of the National Portage Association, told HELLO!: "The Princess wanted to know more about how portage is organised, how it's funded. Is there enough?
"She obviously understood the impact that portage makes on the children, especially in the first five years. The first five years are crucial for any child, but for a child with additional needs and their family, it's even more crucial."
Janet added: "We're hoping that [Kate's visit] is going to be life changing. We really hope that it will showcase what we do and the impact that we have as British practitioners on children's lives and the lives of their families."
Kate's visit to the centre in Kent was the first in a series of Shaping Us engagements that will run from now until Christmas, with the focus being on children and families.
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