Hollywood Moms React to Super-Fit Pregnant Model Sarah Stage

This video is unavailable because we were unable to load a message from our sponsors.

If you are using ad-blocking software, please disable it and reload the page.

Plenty of people have an opinion on 30-year-old model Sarah Stage, who's become an Internet sensation thanks to her super-fit baby bump.

Can you tell she's 8 and a half months pregnant?!

PHOTOS: The Most Adorable Celebrity Kids

ET caught up with Hollywood moms Vanessa Lachey, Molly Sims and Rachel Zoe at renowned OB/GYN Dr. Michele Hakakha's book release party for Expecting 411: Clear Answers & Smart Advice for Your Pregnancy on Sunday, where they weighed in on the controversial model.

"She's not normal! It's not normal!" Sims, who's currently expecting her second child -- a baby girl -- with her husband, film producer Scott Stuber, joked.

That being said, the moms also stressed that it's important not to judge.

The 41-year-old Las Vegas actress revealed that she actually gained a significant amount of weight during her first pregnancy with her son, Brooks Alan Stuber, whom she welcomed in June 2012.

"My first pregnancy, I gained like 80 pounds. With this one I only gained 35. So it's different," she noted.

For example, 43-year-old celeb stylist Rachel Zoe said that nobody could tell she was pregnant with her first son, Skylar Morrison Berman, until she was seven and a half months pregnant!

"I was panicked," the super-slender Zoe said. "I was like, 'What is wrong?,' and the second one, you get bigger quicker because your body remembers. But the first one, your body is trying to figure it out and make room. Some people are built smaller. I just think your body tells you what you need to do."

Lachey, who just gave birth to her second child with husband Nick Lachey in January, said it's important for other women not to compare themselves.

"I just think for girls looking at that, it's like Rachel said -- A, don't judge -- and B, just know everybody is different because the problem ... I hate that women are looking at that and thinking, 'I never looked like that,'" the 34-year-old television personality expressed. "That's ok! You can't do that."

"She's working out!" Sims echoed about Stage. "A lot of things like Rachel said, she was this girl before she got pregnant, you know what I mean?"

NEWS: Kim Kardashian Says Her Pregnancy Weight Was God's Way of Punishing Her

Check out the video below for some of the best pregnancy announcements of 2014.