To celebrate the special occasion, Hadid, 25, shared a message on Instagram to express her love for her mother, Yolanda.
In the throwback pic, a young Gigi sat on Yolanda's knee. Both were wearing swimsuits and Yolanda was pregnant, presumably with Gigi's sister, Bella.
"Best I could ever ask for," Gigi wrote in the caption. "Happy Mother’s Day to the one I’ll do my best to emulate."
She added: "I love you beyond words @yolanda.hadid you are a superhero!!!!!"
Gigi also shared several photos of herself and Yolanda, also a model, on her Instagram story to show her appreciation.
The supermodel confirmed her pregnancy last month during a virtual visit to "The Tonight Show" with Jimmy Fallon.
"Obviously, we wished we could have announced it on our own terms, but we're very excited and happy and grateful for everyone's well wishes and support," Hadid said.
She added: "Especially during this time, it's a nice silver lining to be able to be home and be together and really experience it day by day."