It looks like the Brown family will be welcoming a daughter!
"It's a GIRL!" Kody tweeted. "Yippie!"
Robyn, 37, and Kody, 46, are part of a polygamous relationship, in which Kody is "spiritually married" to three other women as well -- Meri, 41, Janelle, 46, and Christine, 43.
Kody had been legally married to Meri, however the two got a divorce so that he could marry Robyn, the youngest of his brides.
Between Kody and his four partners, the family has a combined 17 children, and this new addition will make 18.
See photos of the Kody Brown and his famous family:
Kody and Robyn already share one child, 4-year-old son Solomon. Robyn is also mother three other children -- 15-year-old son Dayton, 13-year-old daughter Aurora and 10-year-old daughter Breanna -- from a previous marriage.
It was recently announced that Kody legally adopted Robyn's other children after they were legally wed.
The new addition to the Brown family is due Jan. 7.
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