The Brown family, reality stars of TLC series “Sister Wives,” is adding to its already large brood. Patriarch Kody Brown and his fourth wife Robyn are expecting their second child together.

Robyn married Kody in a spiritual ceremony in 2010, but became his official wife last year. This will be the 18th child in the polygamist family, which also includes Robyn's three children from a previous marriage.

"We are so happy to announce an eagerly expected new member of the Brown family!" the couple told People on Friday.

“I try to always be kind and tender, but when a woman is expecting, you have to be ultra-sensitive," Kody Brown added. "And always do the dishes."

Kody is an advertising salesman with four wives – Meri (married from 1990 to 2014, still spiritually married), Janelle (married in 1993 in a spiritual wedding), Christine (married in 1994 in a spiritual wedding) and Robyn (married in 2010 in a spiritual wedding, officially wed last year). The family resides in Las Vegas. Kody has one child with Meri, six children with Janelle, six children with Christine. This will be his second child with Robyn, plus her three children from her first marriage.

Kody discreetly divorced Meri, his “main” wife, in 2014, to marry Robyn, 37. He allegedly wanted Robyn’s first three children to have security and access to family privileges, such as insurance and benefits, according to TMZ in February.

Season 7 of "Sister Wives" is currently streaming on Hulu with a Hulu Plus subscription. TLC hasn't revealed when the show will return to TLC, according to its Facebook page.