The world of Jeremy and Audrey Roloff is about to get bigger as they await the arrival of a son.
The "Little People, Big World" alums' son will join their 23-month-old daughter, Ember.
In a gender reveal video, the family stands in a field of green grass and people count down to the couple waving sticks that emit clouds of blue smoke. Ember eats a cupcake with blue icing and Jeremy shows ultrasound photos.
"We’re so excited!” Jeremy captioned his post.
Audrey captioned her post, "We are surprised and can’t wait to be a family of four."
Audrey hinted at the reveal in a post on Aug. 15. She shared an adorable family photo inviting everyone to, "Take your guess."
"Pretty soon we get to find out the gender of this precious little love growing inside of me😍 so.... before you find out here soon.... cast your vote in the comments! Will baby #2 be a boy or girl?!" she wrote.
The baby is due in January. The couple announced their pregnancy in July with a photo of the three posing with ultrasound photos.
Jeremy, 20, wrote in his Instagram, "Ember Jean is going to be a big sister! We're very excited to grow our family. Thanks for following our journey and for your continual support of our family."
More big news from 'Little People' stars
The couple's news comes only months after Jeremy's twin, Zach, announced that he, too, is expecting an addition.
Zach and Tori Roloff announced in May that they are expecting their second child, a girl, in November. She will join the couple's 2-year-old son, Jackson.
Tori posted four photos on Instagram featuring Jackson wearing a shirt that said "big brother."
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This article originally appeared on USA TODAY: "Little People, Big World" alums Jeremy and Audrey are having a boy