Big news! Little People, Big World stars Zach and Tori Roloff are expecting their first child together! The couple announced their happy news via a video on TLC.

“We have some really exciting news to share with all of you,” Zach, who is a dwarf, teases in the clip before wife Tori excitedly exclaims, “We’re having a baby!”

The child will be the first grandbaby for Zach’s parents, Matt and Amy Roloff, who are also featured on the TLC show. The former couple — who, like Zach, are dwarfs — run Roloff Farm in Oregon with their four children.

Tori shared the pregnancy news on her Instagram account with a sweet photo of the young couple holding up ultrasound images of Baby Roloff. “Zach and I are SO excited to FINALLY tell you guys the news!” she captioned the photo, which also revealed the baby is due in May. “Thank you so much already for the love and support we have received! This is going to be one fun adventure! #ZandTpartyofthree.”

In addition to the pregnancy news, Zach, 26, told fans in the video how his wife of 15 months told him she was expecting.

“I walked into the house and she had written it on a notepad that she was practicing her calligraphy, so I was reading through this,” he recalls. “On the last page, she wrote, ‘You’re going to be a dad!’ and I skipped right over it. Then she said, ‘Wait, hey, you missed it!’ Then she pulled it back and I read it.”

The soon-to-be first-time parents don’t yet know the sex of their baby, or whether it will be a dwarf like Zach and his parents. (Zach’s siblings are all of average height.)

“I’m super curious to know if it’s going to be a dwarf baby or not,” Zach tells the camera.

But regardless, there’s one thing Tori is already certain about: “We’re gonna be great parents! I can’t wait!” she exclaims in the TLC video.

Season 12 of Little People, Big World kicks off on TLC Tuesday, November 22, at 8 p.m. ET.

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