One dayKate Middletonwill serve her country as Queen, but for now, she takes a very pragmatic approach to her role as a working member of the royal family.

“She knows the importance of the institution and her role to play,” a source close to Kate tells PEOPLE in this week’s cover story. “She knows that being a member of the royal family is a bit like having a contract, you sign on the dotted line and you deliver.”

In the last eight years since marryingPrince William, many think that Kate has done just that. She has impressed royal insiders with her ability to support the work of her husband while continuing to build on her own charitable portfolio in early-childhood education and development.

“Kate is in her element right now, she’s really stuck at it and persevered with what she believes in,” adds the friend.

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Duchess of Cambridge

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Catherine, Duchess of Cambridge speaks to young children as she helps pick Christmas trees for preschool

With William taking on more official responsibilities recently and two major oversees tours planned for the royal parents in 2020, the couple leans on each other and compliments each other’s work.

On Wednesday,the Cambridges attended the Queen’s annual Christmas luncheon at Buckingham Palace. Next week, they will spend Christmas as a family of five at their country house of Anmer Hall in Norfolk.

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Prince William with Prince George and Catherine Duchess of Cambridge Royal family Christmas Lunch at Buckingham Palace, London, UK - 18 Dec 2019

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Their two eldest childrenPrince GeorgeandPrincess Charlotteareexpected to take part in the traditional Christmas Day walkto church with the Queen, where hundreds of fans wait to catch a glimpse of the royal family.

source: people.com