While pregnancy can be full of surprises, Nikki Bella is leaning on her twin, Brie Bella, to guide her. The soon-to-be mom exclusively tells Life & Style that “letting go of vanity” is the best advice her sister has given her throughout the process.

“Being a first-time mom and just as your body changes … It’s not just the outer part but it’s the inner part — your hormones are going crazy,” the 36-year-old adds.

Nikki and Brie Bella with Birdie
Courtesy of Nikki Bella/Instagram

Nikki has been adjusting to the changes in appearance as well. “You, I think, look at yourself in the mirror a lot differently than [other] people do, and I think, you know, also being in the spotlight, it’s just double adds,” the Total Bellas star says.

Because Nikki was a professional wrestler for 13 years, she’s always been used to being in great shape. However, ever since she became pregnant, she’s had to let go of those expectations and accept that it’s OK to look different. “You have no idea how your body is going to adapt, and that’s been really tough on me,” the brunette beauty admits.

Thankfully, she has Brie by side to reassure her. “So, Brie is just constantly reminding me, ‘You’re pregnant. Vanity doesn’t even exist anymore,’ and is trying to just have me be present and appreciate these changes, and it’s tough.”

While Nikki can’t help but worry about her appearance throughout the pregnancy, focusing on her baby makes it easier. “I’m excited for my appointment today because when I see my baby, it’s crazy how all that goes away,” she divulges. “You just look at this thing growing inside of you, and you’re like, ‘Oh my gosh, I can’t believe how I’m so in love with something I’ve never even met!'”

It’s evident Nikki and her fiancé, Artem Chigvintsev, are excited to welcome their first child together. They even know the sex of the baby already, but have decided to keep it a secret for now. “We are saving it to announce on the season finale of Total Bellas,” she reveals. We can’t wait!

Be sure to tune into season 5 of Total Bellas, premiering on E! Thursday, April 2, at 9 p.m. ET/PT.

Reporting by Diana Cooper