Lilibet's adorable first birthday cake had a sweet detail from Harry and Meghan's wedding

Lilibet Diana Mountbatten-Windsor celebrated her first birthday with an adorable pink cake adorned with flowers during her party at Windsor Castle.

The youngest member of the family, who turned one on June 4, enjoyed a delicious custom creation from Violet Cakes Bakery in London during the Sussex's trip to the UK for the Platinum Jubilee.

Owner and baker Claire Ptak shared details about Lilibet's special birthday cake on Instagram, writing: "The inside was the Amalfi lemon and elderflower cake I created for the Duke and Duchess's wedding in 2018, but this time we covered it with a strawberry buttercream specially for Lilibet."

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"It was an absolute pleasure to make this special cake last week for Lilibet's birthday. Wishing her a very happy year ahead!" she added.

At the top of the three-tiered cake was a little banner with the name 'Lilibet' written on it, alongside pink and white peonies.

Ptak also baked the wedding cake for Prince Harry and Meghan Markle's nuptials in 2018 and designed a dessert for the Platinum Jubilee this month.

"Obviously, we were asked to make that cake [for the royal wedding], it was really an honour to make that cake," Ptak told 9Honey.

"And this cake was more of out of appreciation for Her Majesty. I feel like we couldn't let the day pass without creating something really special for her."

Harry and Meghan celebrated Lilibet's first birthday in private during the Jubilee weekend on the grounds of Frogmore Cottage.

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While Prince William and Kate's children Prince George, eight, Princess Charlotte, seven, and four-year-old Prince Louis were not at the event, Lilibet's second cousins Mia, Lena and Lucas Tindall scored invites to the party.

Archie's godfather, Charlie Van Straubenzee, and his brother Tom, godfather to Princess Charlotte, were also invited, The Sun reports.

During the intimate backyard picnic party, guests were treated to face painting, games and of curse, cake.

Following the birthday celebrations, Harry and Meghan released a new portrait of their daughter to mark the milestone.

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The photo shows the red-haired tot sitting on the grass in the grounds of Frogmore Cottage, near Windsor Castle, wearing a pale blue dress and a white headband.

A second photo was also released showing Meghan holding Lili alongside photographer Misan Harriman's wife and their children.

A spokeswoman for the Sussexes said they had been "incredibly touched" by the birthday wishes sent for their daughter.