Maci Bookout is in the hospital ready to give birth to her third child.

Just one day after celebrating her daughter Jayde's first birthday, the Teen Mom OG star's fiancé, Taylor McKinney, announced his soon-to-be-wife was in labor.

"Sitting in the hospital waiting on Maverick watching a live feed of Bentley's baseball game. #GoGetemB #thingsthatmatter #ttmlifestyle," McKinney wrote on Instagram on Monday, along with a screenshot of Bentley's scores.

The previous day, May 29, Bookout took to Instagram where she shared what was likely her final baby bump photo while honoring Jayde's special day.

"Our smart, sweet, and oh so sassy baby girl is a whole year old today! Happy 1st Birthday Miss Jayde Carter, you bring so much love & laughter to our lives!" Bookout wrote in the caption of the photo.

Bookout began dating McKinney years ago and after dropping several not-so-subtle hints regaring her desire to get married, McKinney porposed to the reality star in Januuary.

“I found out I was pregnant with baby number three right after we got engaged,” Bookout told MTV News, according to a report shared by Hollywood Life in February. “It was not expected or a planned pregnancy."

Still, Bookout felt prepared.

"Because it’s the third [baby], you know what’s going on. You’ve been there, done that a couple times now, so it’s sort of laid back,” she explained.

As for cravings, Bookout hasn't had many.

"I think the only thing that’s kinda odd is pineapple,” she continued. “Other than that I’m just hungry all the time. When Taylor found out that we were expecting again, he was excited. Annoyingly excited. And Bentley is really excited, from the beginning. He loves Jayde, but he’s always wanted a little brother.”

For more details on Bookout's pregnancy and her thoughts upon discovering she was pregnant, check out her interview below.

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