Kate Middleton received the sweetest Mother's Day gift this year.

On Sunday, the mom of three and husband Prince William marked the U.K. holiday with an Instagram post that included a photo of Prince George 's card that he made for his mom.

The card depicted a floral arrangement in a yellow vase with a heart.

"To mothers new and old and families spending today together and apart - we are thinking of you all at this difficult time," the caption read.

The post also included a previously unseen family photo of Kate with George, 6, her husband Prince William, and their 4-year-old daughter Princess Charlotte. (Kate and William's younger son, Prince Louis, turns 2 next month).

Throwback images of Kate's mother Carole Middleton and her late mother-in-law Princess Diana were also included in Kensington Palace's post.

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In a recent rare interview with the Happy Mum, Happy Baby podcast, Kate shared details of how she hopes her three children will look back on their childhood.

"Is it that I'm sitting down trying to do their maths and spelling homework over the weekend? Or is it the fact that we've gone out and lit a bonfire and sat around trying to cook sausages that hasn't worked because it's too wet?" the royal said.

"That's what I would want them to remember, those moments with me as a mother, but also the family going to the beach, getting soaking wet, filling our boots full of water, those are what I would want them to remember," Kate added. "Not a stressful household where you're trying to do everything and not really succeeding at one thing."

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Recently, it was announced that George and Charlotte - who are enrolled at Thomas's Battersea - will be continuing their lessons at home moving forward amid the ongoing coronavirus pandemic.

The royal children will now move to "remote learning" and continue their lessons using online sources next week, their school said in a statement last Wednesday.

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