Robyn will reveal some big news to the Brown family in episode 6 of the hit TLC series “Sister Wives” – and we think we know what it is! During episode 2 of the reality series, Kody, the Brown patriarch of the polygamist clan, dished to his fourth sister wife that he wanted to have another baby – something Robyn agreed she was on board with only after making a deal with her husband.

The two decided that they would try to have another child together if Kody agreed to allow his son Solomon to cut his long, blond hair. (Apparently Kody has a thing for long tresses and was traumatized when his sister wives took it upon themselves to cut the locks of his other children without his input.)

“Deal?” he asked Robyn in episode 2.

“I think so. Yeah,” she responded with a giggle.

So, could Robyn’s “big announcement” involve her telling the family that she’s pregnant with Kody’s 18th child? We have a feeling it is! Robyn and Kody confirmed to the public that they were expecting their second child together in June.

“We are so happy to announce an eagerly expected new member of the Brown family,” the twosome told People magazine in a statement.

But Robyn’s pregnancy reveal isn’t the only exciting thing set to occur in the upcoming Season 12 installment. According to the synopsis for episode 6, Robyn and Kody will both take one step closer to adopting Dayton, Aurora and Breanna – Robyn’s three children from her previous marriage.

“The adoption of Robyn's kids nears as the Browns sign the official papers with their lawyer,” the summary states.

The adoption storyline has played a vital – and emotional – part in Season 6 of “Sister Wives.” After getting permission from Robyn’s children and from the birth father of Dayton, Aurora and Breanna, Kody will continue his journey on becoming the legal father of the three. But now there’s one, robe-sporting obstacle that's standing in his way: the judge.

“It comes down to the judge and how he feels about plural families,” Christine, Kody’s third sister wife, noted in episode 4.

Meanwhile, Meri will see a doctor in episode 6 to “discuss her recent weight loss,” the synopsis notes, adding that Kody and Christine will have “another session with a marriage counselor after their trip to Texas.” In episode 3, the couple traveled to Texas to meet with their marriage counselor and discuss their intimacy issues – something that has been eating away at Christine for years. Can the duo finally overcome their relationship struggles in episode 6?

“Sister Wives” airs Sunday nights at 9 p.m. EDT on TLC.