Meghan, who is thought to be six months pregnant, met with staff, volunteers and beneficiaries at the engagement in North West London.
A well-wisher, Peggy McEachrom, appeared delighted to meet the Duchess and said: “You’re a fat lady,” referring to Meghan’s baby bump.
But the Duchess saw the funny side, laughed and said: “I’ll take that!”
A renowned animal lover, the 37-year-old learned about the various initiatives Mayhew runs, including animal therapy visits and work with homeless people and their pets.
CEO Caroline Yates revealed that Meghan was quite taken with a little Jack Russell called Minnie.
“She asked about Minnie’s story, what she’s like and if she’s up for adoption? And she is!”
Meghan rescued her dog Guy from a shelter in 2015 and she and Harry are believed to have adopted a second pup last year.
Today marked her first official as patron to the charity, but she has been visiting them privately since autumn last year.
Tonight she and Harry will attend the premiere of Cirque du Soleil’s Totem at London’s Royal Albert Hall.
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