Gigi Hadid welcomed her first child, a baby girl, with boyfriend Zayn Malik last month

Gigi Hadid is showing off her post-baby body weeks after welcoming her daughter with boyfriend Zayn Malik.

On Saturday, the supermodel, 25, posed for a mirror selfie on Instagram while wearing a Vote T-shirt tucked into a pair of bright yellow pants. In her caption, Hadid urged her followers to vote in the 2020 presidential election on Nov. 3 and included information on when early voting takes place per state.

"I voted absentee last week with my daughter next to me, for an America I want her to see; but not just for us- for fellow Americans that are less privileged, with hope for a nation that is unified, that is empathetic, & for a leader that is compassionate," the new mom wrote.

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On Sept. 23, Hadid and Malik, 27, announced on their respective social media accounts that they welcomed their first child together, a daughter, the weekend prior. "Our baby girl is here, healthy & beautiful," the former One Direction member wrote on Twitter.

"To try put into words how I am feeling right now would be an impossible task," the new dad continued. "The love I feel for this tiny human is beyond my understanding. Grateful to know her, proud to call her mine, & thankful for the life we will have together x."

The model shared another black and white image featuring Malik and their daughter holding hands, writing, "Our girl joined us earth-side this weekend and she’s already changed our world. So in love🥺💕."

Hadid confirmed she was expecting with Malik during an April 30 interview with Jimmy Fallon, telling The Tonight Show host, "Obviously, we wish they could've announced it on our own terms, but we're very excited and happy and grateful for everyone's well-wishes and support."

Sources close to the couple told PEOPLE in May that the couple was "thrilled" about the baby and their next chapter together.

"They've been through their ups and downs, but neither stopped caring about the other," a fashion-world source said. "They've jumped on the timing of having a baby and are preparing for their new lives."