Zach Roloff is going to be a first-time father.
"Hey everyone, we have some really exciting news to share with all of you -- we're having a baby!" the couple said in the post. "It's going to be the first grandbaby on Roloff Farms, and it's coming this spring!"
"Super curious to know if it's going to be a dwarf baby or not, [if it will] come out with some sort of dwarfism. Obviously it's a super emotional time for me," Zach admitted.
Zach and his parents, Matt and Amy Roloff, all have dwarfism and stand under 4'3" tall, while Zach's twin brother, Jeremy, and siblings Jacob and Molly are of average height.
Zach and Tori told People that they "can't wait" to become parents."We are super excited," Tori said. "We are waiting until after Christmas to know the gender to go crazy buying things. We are just enjoying the moment right now."
"I'll be a fun, hands-on dad, but also the disciplinarian," Zach added. "Tori will be a loving mother hen."
"Little People, Big World" premiered in 2006 and will return for an 11th season on Tuesday.