Model Mara Martin Welcomes Baby No. 2 with Fiancé Ryan Vandenburg: 'Instantly Fell in Love' (Exclusive)

The model went viral after breastfeeding her first baby on the runway

Mara Martin is a mom again!

The Sports Illustrated model, who went viral in 2018 for walking the runway while breastfeeding her daughter, has welcomed her second baby, she shares with PEOPLE exclusively.

Martin, 37, and fiancé Ryan Vandenburg welcomed daughter Vera Elise Vandenburg on Friday, August 4, weighing 9 lbs., 9 oz. and measuring 22 in. The baby girl joins big sister Aria, 5.

"There has definitely been a big learning curve for us," the new mom of two shares. "Initially, Ryan and I thought this would be super easy because we've done this before, but we were humbled really quickly with how many diapers newborns go through. And sleep is not an option!"

"For me personally, I have found it challenging to make sure Aria is still getting the attention and love with the baby taking up most of our time."

That said, the 5-year-old "instantly fell in love" with her baby sister.

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

"She was so excited to meet her and when we got to bring her home, I think it really sunk in that this was her new baby sister," Martin tells PEOPLE. "She’s been so helpful with wanting to hold her, change her diapers, and take care of her. I can’t wait to see the relationship grow as they get older. It’s been the most rewarding week of my life."

Martin also praises Vandenburg for being "a great partner through such a vulnerable period."

"Ryan has been wonderful throughout my entire pregnancy, birth, and now as a father of two little girls. Not that I am a week postpartum, recovering from birth, and starting my breastfeeding journey, Ryan has picked up the extra slack by helping in all aspects — whether that be cooking, cleaning, changing diapers, or playing with Aria to keep her occupied."

In February, the couple announced their happy news exclusively to PEOPLE. "We are so excited for baby No. 2," Martin said at the time. "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 added.

While walking in the Sports Illustrated Swim Search fashion show in 2018, Martin breastfed her then-5-month-old, 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 said she "definitely" plans on breastfeeding her second baby.

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

As she and Vandenburg prepared to welcome their new addition, Martin said she thought daughter Aria was 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," said 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."

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Read the original article on People.