Prince William and Kate Middleton's Kids Write Mother's Day Notes to Princess Diana

Princess Diana and royals
Tim Graham Photo Library via Getty Images and Comic Relief/BBC Children in Need/Comic Relief via Getty Images

Sunday, March 14, is Mother's Day in the United Kingdom.

Princess Diana is being honored on British Mother's Day! The late Princess of Wales received a touching tribute from three of her grandchildren -- 7-year-old Prince George, 5-year-old Princess Charlotte, and 2-year-old Prince Louis

On Instagram, Kensington Palace shared the sweet handmade cards from Prince William, and Kate Middleton's kids, writing, "Each year on Mother’s Day, George, Charlotte and Louis make cards remembering their Granny Diana, for William."

In the precious cards, George and Charlotte refer to Diana as "Granny Diana" and Charlotte sweetly writes, "I am thinking of you on Mother's Day. I love you very much. Papa is missing you." 

George also drew a beautiful landscape scene with an impressive tree, black birds, mountains and the sun. 

The Palace acknowledged that the holiday can be a difficult one for many, writing, "This year Mother’s Day will be different once again. Many of us will be apart from our loved ones, but looking forward to a time in the not too distant future when we can give our mother a hug again. But for those experiencing bereavement, today may be particularly challenging."

The family also honored Kate and her mother, Carole Middleton, with a homemade cake and a throwback photo. 

"Celebrating two other special mothers today ❤️ 🎂 made by George, Charlotte and Louis," the Palace captioned the post. 

It's been a difficult time for the royal family in the wake of Prince Harry and Meghan Markle's shocking interview with Oprah Winfrey earlier this month. Both Harry, 36, and William, 38, have admitted that they aren't on great speaking terms at the moment.

"I think everyone hopes that the brothers will be able to heal this rift, clearly it does run deep. I think it speaks volumes that William hasn't yet picked up the phone to call his brother. I think that he's clearly needed some cooling off time," royal expert Katie Nicholl previously told ET of William's reaction to the interview. "I think the feeling though is that time is a healer. That's something that Harry himself said."