Patrick Mahomes Marks Baby Sterling's 1-Month Birthday with Cute Father-Daughter Photo

Patrick Mahomes is one happy #girldad!

On Saturday, the NFL star, 25, and his fiancée Brittany Matthews marked a special milestone as their daughter Sterling Skye turned 1-month-old. In honor of the big day, Mahomes shared a new father-daughter image on Instagram.

"1 month ❤️," the Kansas City Chiefs quarterback proudly captioned the portrait, in which he gives his baby girl a big smile and cradles her in his hands.

"Ster is 1 Month🥺💕," Matthews, 25, also shared the same image on her own Instagram page.

Mahomes and Matthews welcomed their first child last month and announced the happy news on social media. "Sterling Skye Mahomes 👸🏼 2/20/21 6lbs 11oz," Matthews shared on Instagram while Mahomes wrote: "Sterling Skye Mahomes 2/20/21 ❤️."

Also on Saturday, the mom of one shared glimpses of their celebration for their daughter.

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Matthews and her loved ones were at Salt River Fields stadium in Arizona, where the Kansas City Royals played the Diamondbacks for spring training. "Sterling says thank you @KCRoyals," the proud parent wrote on her Instagram Story along with a photo of the venue.

She also shared a photo of the pink and white cake which had "Happy 1 Month Birthday Sterling," written in frosting.

The longtime couple began dating in their teens and got engaged last September, with the quarterback proposing to the former pro soccer player after the Chiefs' Super Bowl ring ceremony.

That same month, they announced the pregnancy news, adding that they were "taking a small detour to the wedding."

Brittany Matthews / Instagram

RELATED: The Most Adorable Photos of Patrick Mahomes and Brittany Matthews Through the Years

Brittany Matthews / Instagram

The couple found out the sex of their baby on the way in October, both embracing and sharing in excitement about expecting a daughter. Prior to that, when asked on The Drive in September whether he was hoping for a son or daughter, Mahomes said, "I'm just super excited to hopefully have a healthy baby and someone I'll be able to love for the rest of my life."

And in December, the NFL star said in an interview with KCSP 610 Sports Radio that the best thing that happened to him this past year was a "tie" between his engagement and the subsequent news that they were expecting.

"Those things are special, that you don't get to happen a lot in your life," he said at the time. "Being able to be a dad and being able to get married here soon, I'm truly thankful for that."