A rep for the model, 27, and her musician husband, 30, confirmed to PEOPLE that the model is just over six months pregnant.
Justin has long been open about his desire to start a family with Hailey, sharing with Ellen Degeneres in 2020 that he was respecting his wife's timeline.
I am going to have as many [babies] as Hailey is wishing to push out," he told the talk show host at the time. "I'd love to have myself a little tribe. But, yeah, it's her body and whatever she wants to do. ... I think she wants to have a few."
"But I think Hailey still has some things she wants to accomplish as a woman, and I think ... she's just not ready yet. And that's okay," he said.
In October 2023, Hailey appeared on the cover of GQ Hype and addressed rumours about her being pregnant.
"When there comes a day that that is true, you, you as in the internet, will be the last to know," she said at the time.
Although she had previously discussed raising her kids out of the spotlight, Hailey also told the publication that it's "probably totally unavoidable. That was before I was married. Didn't know who I was going to be married to at the time, I'm sure."
Explaining that motherhood "is something that I look forward to," she added; "It's also such a private, intimate thing. It's something that's going to come when it comes."
More to come.