Prince George, Princess Charlotte and Prince Louis created cards for their late grandmother on U.K. Mother's Day
Princess Charlotte; Prince William, Duke of Cambridge
Princess Charlotte and Prince William
| Credit: Aaron Chown - WPA Pool/Getty Images

Prince William's children are remembering Princess Diana.

Prince George, 7, Princess Charlotte, 5, and Prince Louis, 2, all created homemade cards to their late grandmother, "Granny Diana," in honor of Mother's Day in the U.K. over the weekend.

Princess Charlotte decorated her pink card with a colorful heart, stickers and a sweet note saying that her father was missing his mother.

"Dear Granny Diana, I am thinking of you on Mother's Day. I love you very much," the young princess wrote. "Papa is missing you. Lots of love Charlotte."

Prince George also penned a messages in his card, writing, "Happy happy Mothers Day. I love you very much and think of you always. Sending lots of love from George."

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Prince Harry honored his late mother by arranging for flowers to be placed at her grave in Althorp, Northamptonshire.

prince harry, princess diana, prince william
Prince William, Princess Diana and Prince Harry
| Credit: Jayne Fincher/Princess Diana Archive/Getty

long-awaited statue to honor Princess Diana is set to be installed this summer on what would have been the late royal's 60th birthday — July 1, 2021. Prince William, 39, and Prince Harry, 36, announced in August that the statue will stand in the garden of their mother's former home, Kensington Palace, and help people "reflect on her life and legacy."

Plans for the statue were first announced in February 2017, the year of many commemorations of Diana's life, as it marked 20 years since she died in a car crash in Paris. She was 36.

Princess Diana
Princess Diana
| Credit: Julian Parker/UK Press via Getty

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The statue was "commissioned to mark the twentieth anniversary of her death and recognize her positive impact in the UK and around the world," the palace said in a brief statement.

"The statue will be installed in the Sunken Garden of Kensington Palace on 1st July 2021, marking The Princess's 60th birthday," the statement continues. "The Princes hope that the statue will help all those who visit Kensington Palace to reflect on their mother's life and her legacy."