Pregnant Ashley Graham Reveals She's Expecting Twin Boys: 'Are You Serious?'

Ashley Graham is about to be a boy mom times three!

The pregnant supermodel, 33, revealed in a video on Instagram Monday that she is, in fact, expecting twin baby boys with husband Justin Ervin. In the video, they shared the moment they found out they were expecting, plus the ultrasound appointment when they learned they had two babies on the way.

"Are you serious? We're gonna have three boys?" she says with a laugh asErvin adds in disbelief, "You are kidding me!"

Graham and Ervin announced in July that they're pregnant with their second child, after son Isaac Menelik was born on Jan. 18, 2020.

"I don't think he understands the concept of being a 'big brother,' " Graham recently told PEOPLE of Isaac. "He knows that there's a baby in the belly. Because I say, 'Where's the baby?' And then he points and then wants to kiss it."

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While discussing her new partnership with Knix last month, Graham told PEOPLE about how her body changes during pregnancy.

"I think being in control when you're pregnant, it just gets thrown out the window," she said.

"And I learned that the hard way when I tried to control everything when I was pregnant with Isaac and I told myself that I was going to bounce right back because I was breastfeeding and everybody told me, 'Oh, if you breastfeed you're going to lose all the weight,' " Graham added. "And I had a few honest women tell me you will never feel the same. So they were just blunt with me and sure enough, I haven't felt the same."

"Then boom. I was like, 'Well, I just got pregnant again so maybe I'll never feel the same and I don't even know what I felt like before I was pregnant with Isaac anyways,' " she said.