Model Mara Martin, Who Went Viral for Breastfeeding on the Runway, Is Expecting Baby No. 2

Helen Le Van

Mara Martin is going to be a mom of two!

The Sports Illustrated model, who went viral in 2018 for walking the runway while breastfeeding her daughter, is pregnant, expecting her second baby with fiancé Ryan Vandenburg, PEOPLE can exclusively announce. Martin and Vandenburg are already parents to daughter Aria, 5.

"We are so excited for baby No. 2," Martin tells PEOPLE. "We had been tracking and trying all of the tricks and tips for almost a year, hoping to get pregnant again, so when we found out, we were absolutely thrilled!"

"In some ways, it feels like it's my first time all over again because it's been over five years since Aria was born, but her excitement makes it really fun and different this time around," she adds.

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RELATED: Breastfeeding Model 'Proud' to Represent Moms — Despite Critics Calling Her 'Unprofessional'

While walking in the Sports Illustrated Swim Search fashion show in 2018, Martin breastfed her then-5-month-old daughter Aria, telling PEOPLE at the time she was "proud" to represent working moms in that moment.

While Martin "doesn't know if I'll breastfeed on the runway again," she says she "definitely" plans on breastfeeding her second baby.

Helen Le Van

"We'll see how it all goes — the important thing is that my baby is fed and loved," she says. "I had such an amazing experience breastfeeding Aria, so I'm hoping to share that bond again."

"At the same time, I'm not going to be too hard on myself, and I'm ready to roll with whatever happens. Doing what's best for you and your family is the most important thing, not the stigma and outside pressure of breast versus bottle feeding," she adds.

Frazer Harrison/Getty

As she and Vandenburg prepare to welcome their new addition, Martin says she thinks daughter Aria is the "most excited of all."

"She's been talking nonstop about being a big sister since the day she found out, telling everyone we see, and practicing with her baby dolls," says the model. "She even let the secret slip out to some family sooner than we planned on announcing it because she starts her conversations by blurting out, 'Hi! Mama has a baby in the belly!' It's the sweetest thing to see."