Robyn and Kody Brown Credit: Ben Dome/Nate Jones/PacificCoast

Sister WivesRobyn Brown and her husband, Kody, have chosen a name for their 6-day-old daughter: Ariella Mae, TLC confirms to Us Weekly.

Ariella was born on Sunday, January 10, weighing 9 pounds, 9 ounces, and measuring 21.5 inches long. The reality stars, who were legally married in 2014, are already parents of a 3-year-old son, Solomon.

Kody’s polygamous family includes three wives — Robyn, Christine and Janelle — and a total of 18 children, including their newest bundle of joy. Robyn is also the mother of three children from a previous marriage — Dayton, 15, Aurora, 13, and Breanna, 10.

In November, Kody tweeted his excitement after the couple found out the gender of their new baby. “It’s a GIRL!!!” he wrote. “Yippie!”

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