Last night's episode of Sister Wives focused on blending the fourth wife — and her children — into Kody's family. So far we've seen how the adults are dealing — but what about the kids?

Kody has been married to Meri for 20 years; they have one daughter. He's been married to Janelle for 17 years, and they have six kids. Christine, the third wife, has been married for 16 years; they have five children and one on the way. Robyn, who will be Kody's fourth wife, is divorced with 3 kids, and about to turn 30.

Kody asked some of the older daughters to help plan Robyn's birthday party, which gave the teenage girls a chance to express their feelings about bringing a new wife/mother into the family. Mykelti, 13, seems to think it's a little bit gross that this woman smells her jacket and says stuff like, "I miss your dad." Mariah, 14, squicks out: "she could be my sister." Madison, who is 14, says: "I love Robyn… but if he was my husband with another woman, I would rip her hair out."

Moving Robyn and her kids up near Kody and his family was an ordeal. She can't live in the house with the other wives until she and Kody are married, because "that's not proper." But organizing all the kids, wives and stuff involved was, in Kody's words, "a goat rodeo."

Robyn's birthday — with tons of kids, cake, ice cream and balloons — made having a huge family seem like fun. Meri gave Robyn a friendship necklace, and it was clear that the other wives think Robyn is great. But Madison, one of the most outspoken of the offspring, has it clear in her mind that while she loves her family, she does not love polygamy.

It would be interesting to find out how many kids raised in polygamous families decide polygamy is not for them. Obviously some become so indoctrinated with "the faith" that it makes perfect sense. Also, when you're young and there's always someone to play with or help out, it seems like oodles of fun to have 15 brothers and sisters. But being investigated for felony bigamy? Not as fun.

Sister Wives [TLC]

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