Taking to Instagram, Kate posted three photos she took recently in Norfolk during a family outing to the Big Butterfly Count.
In one image, Charlotte looks adorable as she delicately holds a butterfly in her hand while wearing a blue T-shirt with frill sleeves and cute pink patterned shorts.
WATCH: Kate Middleton tests her reaction skills in fun clip
Captioning the photos, the Duchess wrote: "We wanted to share these beautiful Peacock and Red Admiral butterflies as part of Big #ButterflyCount initiative taking place across the UK.
"@savebutterflies are encouraging us all to count these incredible creatures because not only are they beautiful creatures to be around but they are also extremely important. Butterflies are vital parts of the ecosystem as both pollinators and components of the food chain.
"Hopefully you can beat last year's total, @savebutterflies."
Princess Charlotte looked beautiful in Kate's new photo
Fans were quick to react, with one commenting: "So lovely [love] the world in tiny hands." A second wrote: "How perfect," and a third added: "Wow, so beautiful."
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Kate is a keen photographer and will often take official portraits of her children. On Friday, it was revealed that her moving photographs of two Holocaust survivors with their grandchildren have been included as part of a new photography exhibition at the Imperial War Museum in London.
Kate took the powerful images of Yvonne Bernstein and Steven Frank at Kensington Palace in January 2020, marking 75 years since the end of the Holocaust.
The Duchess said at the time that Yvonne and Steven were "two of the most life-affirming people" she had ever met and that their stories would stay with her forever.
Kate's moving portraits are on display in the new exhibition
In a social media post, which showed the photographs on display and a behind-the-scenes snap of the Duchess talking with Steven and his granddaughters, Kate said: "Honoured to be part of the new photography exhibition at @ImperialWarMuseums in London, bringing together over 50 contemporary portraits of Holocaust survivors and their families.
"Displayed for the very first time, these powerful photographs capture the special connections between Holocaust survivors and the younger generations of their families, and remind us of our collective responsibility to ensure their stories live on.
"The photographs present a group of survivors who made the UK their home after beginnings marked by unimaginable loss and trauma. While offering a space to remember and share their stories, these portraits are a celebration of the full lives they have lived and the special legacy which their children and grandchildren will carry into the future."
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