The royal couple met families from the Welsh Guards, Coldstream Guards and Household Cavalry at Windsor's Broom Farm Community Centre.
Meghan also revealed that their son Archie Harrison has started crawling and has two teeth.
Fellow mum Amy Thompson who attended the event revealed the exciting news to HELLO!.
"My daughter Aeris is the same age as Archie and we talked about weaning and the children beginning to crawl - she's just a normal mum and it was like talking to a friend,” said Amy.
The former actress then revealed that her five-month-old has got two teeth.
"Archie just got two teeth - tiny ones right there,” said Meghan who was remarking on one youngster's teeth.
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