Gigi Hadid and boyfriend Zayn Malik welcomed their first child, daughter Khai, in September
Gigi Hadid
Gigi Hadid and daughter Khai
| Credit: Gigi Hadid/Instagram

Gigi Hadid is celebrating a milestone moment in her life.

On Sunday, the supermodel, 26, commemorated her first Mother's Day since welcoming daughter Khai in September. "The rumors are true: my best friend, purpose, muse, greatest pride & joy! I feel so lucky and inspired bein your mama, my Khai!!" Hadid captioned her Mother's Day post.

"An old soul full of sunshine, you light up everyone's days! Thank you 🧡 thank you 💛 thank you," the mom of one added of her baby girl.

Hadid also gave a shout-out to her mother Yolanda Hadid with throwback photos of the Real Housewives of Beverly Hills alum. "Life! Miracles! MOTHERS! Cheers to our angels above & to you @yolanda.hadid, the most inspiring mama and best Oma we could ever ask for! We love you more than words. Eternally grateful," the first-time mom said of her own mother and late grandmother.

In addition, Hadid shared a new photo of Yolanda holding her first grandchild Khai in her arms. Also on Sunday, Yolanda marked Gigi's first Mother's Day on her Instagram Story with a photo of baby Khai's little feet.

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This time last year, while Hadid was still pregnant, she shared an emotional tribute to her "superhero" mother. 

"Best I could ever ask for. ❤️," she captioned a throwback image of her and a then-pregnant Yolanda sitting on a beach together."Happy Mother's Day to the one I'll do my best to emulate. I love you beyond words @yolanda.hadid you are a superhero!!!!!" she added. 

RELATED VIDEO: Gigi Hadid Calls Daughter Khai Her 'Big Girl' in Adorable New Photo

Hadid and boyfriend Zayn Malik, 28, welcomed Khai, their first child together, last September.

"Our girl joined us earth-side this weekend and she's already changed our world. So in love," Hadid wrote on social media at the time alongside a black-and-white snap of Malik and their daughter holding hands.

In February, Hadid also celebrated another meaningful milestone with her daughter: her first solo Vogue cover

"Who would have thought I'd be feeding my baby girl her morning bottle as we share my first @voguemagazine solo cover?!" the new mom wrote on social media at the time, celebrating the release of the March 2021 issue.

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"I am emotional and honored to take my first professional step, in this new chapter of womanhood, with this dream come true!" she added. "Khai is now rockin' in her Nemo bouncer so I can type this, and I'm reflecting on all the people, memories, flights & fittings, early mornings, late nights, laughs & tears, mishaps & miracles that have made up my almost-decade in fashion."

Making a playful comment about the realities of new motherhood, Hadid ended her note with a candid comment, dedicating the cover "to all the moms who haven't brushed their hair in a couple days, either!"