Leaving her three children Prince George, Princess Charlotte and Prince Louis at home, the Duchess of Cambridge bonded with other adorable youngsters during an engagement in London. Kate visited the Henry Fawcett Children's Centre to learn more about the work being done by local organisations in Lambeth to support young children and their families.
Kate visited the centre to see how the Lambeth Early Action Partnership is using the Parent and Infant Relationship Service to support parents, carers and their children. The scheme is funded by A Better Start, which Prince William and Kate learnt about during their visit to Blackpool last week.
Let's take a look at the best photos from Kate's day out in London….
The Duchess surprised fashion watchers, by switching her go-to dress for a trouser and blouse combo. Kate wore a purple shirt by Gucci and wide-legged trousers by Jigsaw.
Kate sat in on a 'Together Time' session, where parents can come with their children and learn from each other and childcare professionals about everything from bath time to breastfeeding.
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Kate was introduced to 23-months-old twins Kamina and Kashay, whose mother Finesse called them "divas in the making" and "double the trouble".
The royal swapped anecdotes with mum Kriti, who was there with her son Kameron, nine months. "Louis just wants to pull himself up all the time," said Kate of her youngest child, baby Prince Louis. "He has got these little walkers and is bombing around in them."
Kriti said afterwards: "She took one look at Kameron and said 'Oh he wants to go walkies.' Apparently, her son is cruising (when a child pulls themselves up and uses furniture to move about) and she said she was running after him all the time."
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LEAP was set up in 2015, with the help of the National Lottery Community Fund, to test new ways of strengthening support services for families with children aged zero to three. It helps with everything from practical advice to psychotherapy and speech and language support.
The Duchess looked particularly entertained by one little boy.
Prince William's wife is focusing her work on the early years of a child's development.
What a lovely engagement for the Duchess and mother-of-three!
The mum-of-three also sat in on a 'Circle of Security' session, where fellow mothers can talk about their struggles.