The royal kids were filmed picking out presents to go in gift bags sent out from one of the banks, before choosing clothes that would be given to those in need.
Their visit came as Kate encourages the country to donate items as part of the Christmas Baby Bank Initiative.
In a short video released on the Kensington Palace Youtube channel, she reminds her daughter and two sons that children their age benefit from the banks.
‘What we would like you to do is try and choose some presents for some children who are a similar age to you guys,’ she says.
‘So, if you think about what you would like to play with.’
Charlotte is shown laughing as she picks up a baby’s romper suit decorated with red Welsh dragons, before calling out: ‘This is Welsh!’
Later, Kate tells George: ‘You can see how rewarding this kind of work is, knowing that you’re helping others.’ The Prince replies: ‘Yeah.’
The young royals picked out cuddly toys and clothes to put in the gift bags (Picture: @willwarr)
Princess Charlotte was delighted by a Welsh dragon romper suit (Picture: @willwarr)
The Christmas Baby Bank Initiative is being run with the Princess of Wales’ Centre for Early Childhood, which was established in June 2021.
In a post on social media, Kate and William said: ‘Our experiences, relationships and surroundings during early childhood lay foundations that shape the rest of our lives, and future society.
‘Supporting parents and carers, who are providing for their families in challenging circumstances can have a life-changing impact.’
The launch of the new scheme comes two days after the family released their Christmas card picture, which shows them dressed smartly in white shirts.
Some people who saw the picture online spotted some odd quirks, with some even suggesting it was Photoshopped.
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