"I'm so excited to be August's mum," Princess Eugenie said
Princess Eugenie
Jack Brooksbank, Princess Eugenie and their son August
| Credit: Princess Eugenie Instagram

Happy Mother's Day, Princess Eugenie!

In honor of the annual holiday, which is known as "Mothering Sunday" and celebrated in the U.K. this year on March 14, Eugenie, 30, shared a sweet snapshot of her newborn son, August Philip Hawke, in honor of her first-ever Mother's Day.

The royal shared a photograph of August laying in a field of daffodils with his head turned away from the camera, and also posted a throwback photo of her and her mother, Sarah Ferguson.

"I'm so excited to be August's mum and as you can see I'm enjoying my first Mother's Day," the mom of one wrote. "I'm also celebrating my beautiful Mumma with this picture of us from March 1990. You've taught me so much."

"Happy Mother's Day to all 💐," Eugenie added.

Last month, Eugenie and her husband, Jack Brooksbank, welcomed their first child on Feb. 9.

"Her Royal Highness Princess Eugenie was safely delivered of a son today, 9th February 2021, at 8: 55 a.m. at The Portland Hospital," the palace said in a statement at the time, adding that Brooksbank was present for the birth.

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Eugenie also shared a photo announcing the arrival of her son to her Instagram account that same day.

Sharing a black-and-white photo of the new baby's hands in his parents, Eugenie captioned the post simply with three blue hearts.

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A few weeks later, Eugenie and Brooksbank revealed the name of their baby boy on Feb. 20.

"We wanted to introduce you to August Philip Hawke Brooksbank," Eugenie captioned the post, which includes three new photos of the couple and their son.

"Thank you for so many wonderful messages. Our hearts are full of love for this little human, words can't express. We are excited to be able to share these photos with you,⁣" she continued.

The family of three is currently living near her grandparents at Frogmore Cottage — the Windsor home of Prince Harry and Meghan Markle. The Sussexes lent Eugenie their home, which is close to Windsor Castle, where the monarch and her husband have been staying amid the pandemic.

August is the ninth great-grandchild for Queen Elizabeth and Prince Philip and the first grandchild for Eugenie's parents, Prince Andrew and Ferguson, 61.