Pregnant Chanel Iman and Fiancé Davon Godchaux 'Always Talked About Having a Family' (Exclusive)

The supermodel is welcoming a baby with fiancé Davon Godchaux, joining her two daughters, Cassie and Cali, from a previous relationship

Chanel Iman is opening up about her growing family.

Speaking with PEOPLE about her recent collaboration with Cupshe for the swimwear brand's BeMe: The Cupshe Birthday Collection, the supermodel, 32, shared new details about her engagement and current pregnancy.

"It was beautiful," Iman tells PEOPLE of her oceanside engagement to New England Patriots defensive tackle Davon Godchaux, 28. "It was definitely something that was a surprise. My fiancé knows I've already dreamed of going to Capri. And I was going over there on a babymoon. I came back a fiancée!"

Since the engagement is so new, Iman reveals that she hasn't had a chance to tell her kids just yet. "But I will," she assures. "They've been away from me just because they were with their father for the weekend. But I get them back soon. I'll be sharing the exciting news."

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Related: Chanel Iman Reveals She's Having a Baby Girl in Photoshoot with 2 Daughters: 'You're Getting a Sister!'

Iman is already mom to two daughters, Cassie, 3, and Cali, 4½, with ex Sterling Shepard, and is currently expecting another daughter with Godchaux.

"I feel like I know right away," Iman says of finding out she was pregnant. "I know the minute I miss a period, I'm like 'Oh God.' I know what this is because I've done this twice already. I really didn't even need to take a pregnancy test because I already knew."

"The minute I told my fiancé, he was beyond excited because he has one son and I have two daughters. We both have wanted, not a big family, but we've wanted a few more children. When we met each other, we always talked about having a family."

"My fiancé has always wanted me to be his wife. I think this was something that we wanted together and to build a family."

Iman explains that while being pregnant on vacation, she's had a hard time finding swimwear that made her feel comfortable and has been relying on Cupshe for their diversity. "It is sometimes hard to find things that you feel comfortable or confident in on the beach," she says. "It was a perfect fit because I am pregnant."

As for her comfort levels, Iman says she's "out of my first trimester" but still dealing with some nausea.

"With both of my other daughters, I was fine after my first trimester but with this one, my third born, she's making me still very nauseous."

"But I'm so used to being a supermom, already having two, especially a 4-year-old that's going to be 5 and a 3-year-old, I just continue to keep going. I'm sick for one second, I go to the bathroom, do what I have to do. I'm just like, 'All right. Done. All right.' I think my body's gotten used to this whole pregnancy thing. As queasy as I am sometimes just keeping up with toddlers, I just keep it going."

As she looks ahead, Iman says there's one thing she cannot wait for when her baby arrives. "I am most looking forward to sushi," Iman admits. "I've been craving sushi. That's something I cannot eat. Everything that I can't eat, I want to eat."

"My fiancé said that once I have our child, he will make sure that I will not be eating hospital food. But he will have a delivery of Nobu. He'll go to Nobu and deliver it to me. Or Sugarfish!" she exclaims.

And while she's excited to meet her newest addition, the model has been taking time to both teach and learn from her two toddlers.

"My daughter Callie, she's done so well in school," Iman shares. "She teaches me some things sometimes. She's such a smart child. I feel like she's teaching me Spanish right now."

"I'm teaching her to read English, but she's teaching me how to speak Spanish. I think it's fun as a mom to watch my children grow and the things that they can teach you as well."

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Read the original article on People.