Former Little People, Big World stars Jeremy and Audrey Roloff welcomed their first child in September 2017

Jeremy and Audrey Roloff Expecting Second Child: 'We Are So Grateful'

Their world continues to grow!

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“Baby #2 is coming in January!!!🎉 Ember is gonna be a big sister!😍😭 We are so grateful and excited for this little blessing to join our family,” the second-time mom-to-be captioned snapshots of the couple and their daughter posing with ultrasound photos.

On his own Instagram, Jeremy shared a series of photos, writing, “We’ve got some exciting news: 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.”

The new baby will join 21-month-old big sister Ember Jean.

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Days ahead of their pregnancy announcement, Audrey got candid on Instagram about the struggles they face as a couple.

“We fight, struggle, cry, and face challenges just like anyone,” she captioned a lengthy post. “I’m saying this here because if you look at my Instagram feed from the past 3 weeks you don’t see the long tearful conversations, the hurtful remarks, the compiling complaints, the critical spirits, the prideful inner dialogue, or our unloving and disrespectful attitudes. You don’t see the full picture.⁣”

The Roloffs have been open about showing off photos of their daughter and discussing the highs and lows of becoming first-time parents since Ember’s September 2017 birth.

Image zoom Audrey Roloff/Instagram

On an episode of Little People, Big World, Audrey, 27, revealed that she developed mastitis — an infection of the breast tissue — five days after her daughter was born, and dealt with “blistering and bruising” as a result of breastfeeding.

“At our 1-week doctor’s appointment I was like, ‘I’m nursing every hour all night,’ and he was like, ‘That’s not right,’ ” she recalled. “At that point, they were like, ‘You need to supplement, ’cause you’re not giving her enough.’ ”

“I was very adamant about breastfeeding exclusively. Formula was, like, a sin,” Audrey continued with a laugh. “I just never thought I would do that but at the same time, I need to feed my baby, so we have to do it.”

RELATED VIDEO: Little People, Big World‘s Jeremy and Audrey Roloff Welcome Daughter Ember Jean

After 14 years and 17 seasons on the TLC series, Jeremy, 29, announced on Instagram last July that he, his wife and their daughter would be departing the reality show.

“It has been an amazing run, and I can’t say thank you enough to all of you who have watched and supported us along the ride,” he wrote. “We have the most loyal fans on TV and we appreciate every one of you. You are what made doing this so fun.”

Hours later, Audrey praised Jeremy’s decision in a supportive Instagram tribute, thanking their fans for “the encouragement, kindness, and support that each of you have shown to our family.”