Baby boy Brush is one month away from making his debut!

Sister Wives star Maddie Brown is currently pregnant with her first child with husband Caleb Brush — and she’s sharing an exciting baby bump update along with an update on her pregnancy. The 21-year-old is now only four weeks — or one month — away from her due date!

In the adorable photo, Maddie is sitting across from her sister Aspyn Brown while she places her hands on Maddie’s growing baby bump to feel little baby boy Brush kicking around in his mommy’s tummy.

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“[Aspyn] feeling all of his movements, [and] Caleb explaining how baby is sitting,” she wrote in the caption, then added the hashtags “#36weeks” and “#RunningOutOfRoom.”

Maddie and her husband tied the knot together last June and fans got to follow along on their wedding planning on the TLC series Sister Wives — which documents the lives of the polygamous Brown family. Maddie is the daughter of patriarch Kody Brown and his second wife, Janelle Brown. Kody has three other wives, including Meri Brown, Christine Brown, and Robyn Brown.

They announced that they were expecting a boy in an adorable gender reveal party back in January — complete with adorable blue balloons. Their baby marks the first grandchild for the Brown family and the new parents-to-be opened up about how they felt when they found out they were expecting.

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“We are both really excited and anxious,” Maddie told People at the time. “I think every soon-to-be parent is anxious, but we have so much support from both sides of our family.”

Maddie is due on May 20 — which is coming up pretty quickly — and she gushed over what kind of parents she and her husband will be once their bundle of joy arrives.

“I think I’ll be the disciplinarian parent just because Caleb already has such a soft spot for the baby,” she revealed. “He already ha so much love for the baby.”

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