The famously hands-on grandmother to royal children Prince George, Princess Charlotte and Prince Louis secretly cared for a local resident stricken with COVID-19 near the family's home in Bucklebury, Berkshire, around 50 miles west of London.
"Her neighbor was very ill with the virus, and she visited them with homemade soup every day,” a close source tells PEOPLE. “She just left it on their doorstep and nobody knew about it.”
The mom of three and grandmother of four (including Pippa's son Arthur) "just did it because she felt it was the right thing to do,” adds the close source. The neighbor has since made a full recovery.
Speaking exclusively in this week's PEOPLE cover story, the close source also says the portrayal of Kate's mom as pushy in a recent edition of the U.K.'s Tatler magazine is "undeserved."
"There is no way you would describe her as that," the close source says of Carole, 65. "She's an incredibly kind person."
That kindness is reflected in future Queen Kate, 38, who is "relishing her role more than ever," says the source. "And she will do it all to the best of her ability."
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The source continues, "Catherine is the sort of woman who will take on whatever she needs to. If she needs to step up to the plate, she does it — and she always has."