WATCH: Duchess Kate and Princess Charlotte share a sweet mother-daughter moment
The photograph was taken in Norfolk by the Duchess, who is a keen photographer, and showed a smiley Charlotte sitting surrounded by wildflowers, wearing a pretty blue jumper over a white blouse and with her long hair flowing past her shoulders.
Royal blog account, loopycrown3, has shared the photo of Prince William and Kate's sweet thank you note on Instagram. The heartwarming message read: "Thank you for the kind birthday message which you sent for Princess Charlotte's seventh birthday.
"Princess Charlotte had a lovely day and your message was greatly appreciated by The Duke and Duchess of Cambridge who send you their very best wishes."
The photo of Princess Charlotte shared Photo credit: Duchess of Cambridge
Charlotte has had a busy time over the last few weeks, attending several events over the Queen's Platinum Jubilee. She will no doubt be looking forward to a relaxing summer ahead with her brothers Prince George and Prince Louis.
Charlotte and George, aged eight, broke up from their school Thomas' in London's Battersea on 8 July, while four-year-old Louis' nursery school Willcocks finished for the summer on 6 July.
The Cambridges usually visit the Queen in Balmoral, Scotland in August, so it's likely they'll be spending a few days there later this summer. The family have previously flown on commercial flights to reach Aberdeenshire. It's an exciting time for William, Kate and their young children.
The family are said to be relocating to Windsor this summer to be closer to the Queen and Kate's parents Carole and Michael Middleton, who live in Berkshire.
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