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Serena Williams' 2nd Birthday Post For Olympia Is *So* Sweet

Any parent can tell you, you blink and suddenly your little one isn't so little any more. Just like that, Alexis Olympia is already turning two! And, as to be expected, Olympia's 2nd birthday is giving Serena Williams all the mom feels. Looking back on the beginning of your child's life brings up a mix of feelings of nostalgia, accomplishment, love and even a little sadness for the loss of those bittersweet newborn days. On the occasion of Olympia's 2nd birthday on Sunday, Williams is feeling proud — and rightfully so.

In an Instagram post for the special day, Williams shared a photo from the day Olympia was born and wrote, “The last 2 years have been my greatest accomplishment," according to People, and she certainly has a lot to be proud of. Between the trials and tribulations of bringing up a baby — it is hard, y'all — and being an overall beast in her tennis career while running a fashion line, serving on the Board of Directors for PoshMark, and much more, I'd say she's kicking butt. And, not least of all, she's raising a pretty adorable little girl.

Olympia's dad, Alexis Ohanian, also took the chance to celebrate two years of parenthood with an Instagram post of his own, mentioning the importance of paid parental leave. "How has it already been two years?," he wrote. "Happy cake day @olympiaohanian Thank you for being the greatest thing we've ever done. And thank you for teaching me that every parent in the US deserves those first months with their newborn. I'm a better business leader because of it. #PaidFamilyLeave."

Williams has been consistently transparent about her questions, struggles, and successes as a mom, allowing her many fans to follow her motherhood journey closely. A common theme in her posts to social media is the pain and guilt of being away from Olympia — something that many working moms can relate to. Williams spent some of Olympia's 2nd birthday working, in fact, as she participated in the U.S. Open tournament and played against Croatian player Petra Martić on Sunday afternoon, according to the New York Post.

While she loves a good match, Williams often leaves Olympia to play with a heavy heart. Speaking with Forbes last month, Williams told the outlet that it can be “painful” to be away from her daughter during long tournament days:

In the beginning she would really be upset when I left. Now she’s a little bit better. I think I’m a little more upset. But at the same time, she definitely still takes it a little hard. She’s still super young.

She went on to explain that despite the emotional toll being away from Olympia takes on her, it comes with the territory of being a working mom. "Sometimes my heart literally aches when I’m not around her," she told Forbes. "But, you know, it’s good for me, I guess, to keep working and just — to all moms out there that it’s not easy. It’s really kind of painful sometimes. Sometimes you just have to do what you have to do."

But thanks to super awesome dad Ohanian, Olympia often gets to tag along to her mom's matches. In December, the little cheerleader was even caught on camera clapping for her mom while she competed against Aunt Venus, as Buzzfeed News reported. Now Olympia is also attending the U.S. Open with her mom and dad as well, as TMZ reported, and even got to enjoy a petty cab ride around New York City on Saturday during Williams' break in competition.

It's only natural for a milestone like a second birthday to bring up the mix of emotions that come with motherhood. When she looks back on her first two years as a mom, Williams should absolutely feel pride. "Sometimes I get really down and feel like, 'Man, I can't do this,'" she told Vogue for her Motherhood cover story last year. While those feelings are all too common, she is doing it — and Olympia is now two whole years of proof.