Serena Williams Celebrates One Year with Baby Girl Adira as She Shares Throwback Pregnancy Photos: 'A True Light'

Serena Williams is reminiscing on an important day in her life.

On Thursday, Aug. 15, the retired tennis pro, 42, shared a couple of posts on her Instagram as she took a minute to share that it has been a year since she welcomed her daughter Adira. Williams first shared a series of photos from her maternity shoot, which showed the mom of two wearing a see-through, flowy pink dress and lying on a bed of flowers.

Williams also included photos of herself in a sports bra, showcasing her bare bump in black-and-white photos.

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"A year ago today - August 15th - I gave birth to my second baby girl, Adira River Ohanian. She is a true light. Here’s a peek inside my maternity shoot. @adiraohanian," Williams wrote in her caption.

In her second post, Williams posed with daughter Olympia, 6, and husband Alexis Ohanian, with Olympia kissing her mom's stomach. She also shared a photo of her side profile, putting her two hands on top of and below her bump.

"Adira is a girl’s name of Hebrew origin and means ‘mighty,’ ‘strong,’ and ‘majestic.’ The elegant name is popular in many cultures around the world," Williams shared in her second post. "Adira is the feminine form of the classic name Adir. It is a Biblical name, meaning ‘Strong One.’ @alexisohanian @olympiaohanian."

Speaking to PEOPLE in May, Ohanian shared that he's excited to see his younger daughter start to get her footing, noting it's "fun because she's getting more mobile."

"She's able to have a lot more fun with her sister in terms of playing. You can already see the interactions between them. It's a big age gap, and Olympia has a little bit of that maternal spirit. She's like, 'This is my baby,' and it's great to see them together," Ohanian shared.

"They play and sort wrestle and all that. We're very lucky because Adira's got a great personality and Olympia does too, plus she's so excited to be a big sis. So seeing the two of them interact with each other has been a special kind of fun. Adira's getting more mobile and ore vocal, and it's only going to get even more fun."

He joked, "I guess at some point they're going to fight over things, but for now, let me live in bliss."