‘Sister Wives’ Season 6 Spoilers: Kody and Christine to Address their Marriage Problems

Kody Brown and his third wife, Christine, will finally address their marriage troubles in this week's "Sister Wives" season 6 episode.

According to the spoilers, the couple, who are spiritually married - Kody, 46, is only legally married to his fourth wife, Robyn, 36 - will be heading to Texas to celebrate their anniversary. The trip, however, turns into a session of couple's therapy when they start to discuss their recent issues.

Although viewers are not sure why Kody and Christine, 42, have been arguing, many are speculating that Christine might be fed up with Kody's lack of attention. Since Kody legally divorced his first wife, Meri, 46, in order to marry Robyn and adopt her children, he has not had a lot of time to spend with Christine.

Back in season three, Christine also voiced her concerns over his union with Robyn.

"To me, I don't think Kody is very equal with his time," she had said. "I think he caters to Robyn. To Robyn's needs, to Robyn's kids. And I think he's spending all his time building up his and Robyn's and he doesn't realize that our relationship really is not great. And he needs to spend some time developing our relationship too."

Kody and Robyn's marriage might also be taking a toll on Meri, who has stated that she does not want to attend their wedding because she thinks it would be weird. Robyn, however, reportedly really wants Meri to be there because she helped give Kody the opportunity to adopt her children by agreeing to divorce him.

The episode of "Sister Wives" will air this Sunday at 9 p.m. ET on TLC.