It’s a girl!

Teen Mom OG‘sCatelynnandTylerBaltierra are expecting a daughter, the couple revealed on Instagram Wednesday.

To share the sex reveal, the pair each posted a photo to Instagram of their 3½-year-old daughterNovalee Reignholding up a “big sister” sign.

“I am such a pretty little girl my mommy & daddy wanted another one to be their world,” the sign reads. “So as our world gets a little bigger I just can’t wait to be a big sister.”

“I was so shocked that it was a girl because I for sure thought it was a boy!” Catelynn, 26, toldUS Weeklyabout learning that she was expecting another daughter. “Tyler knew the sex before I did. When we did our gender reveal, I was so shocked I almost cried because I wanted a boy so badly.”

Despite her initial hope for a son, the mom of two said she couldn’t be happier.

“I’m super excited it’s a girl now,” she said. “Since our miscarriage, I just am thankful to get another chance, and as long as it’s healthy, that’s all that matters.”

“We definitely want to have a boy, but if God only wants us to have girls, then that’s just what it is,” she said. “It will be a houseful of all girls! Poor Tyler!”

Kevin Mazur/WireImage

2015 MTV Movie Awards - Red Carpet

Catelynn and Tyler are also parents to 9-year-old Carly, who they placed for adoption in 2009.

On Tuesday, Tyler shared an adorable video of Nova holding and kissing a sonogram of her little sister.

Nova couldn’t contain her excitement and happily said, “It’s waving to me!” as she kissed the photograph of Catelynn’s scan.

In an interview with PEOPLE in September, Catelynn said she was putting her pregnancy “in God’s hands.”

“I think it’s always going to be in the back of somebody’s head when you struggle, like, with a miscarriage,” Catelynn said. “But I mean, I was just — I put it in God’s hands, really. Whatever happens is meant to happen and I just kind of go with whatever His plan is.”

source: people.com