Married Couple can only Offer Massage?

My two sims, Phoenix and Kenzie are married, they have two daughters, they are custom sims with no parents that I made and therefore shouldn't be related.

At some point, after having the kids, I noticed that there were no romance options other than Offer Massage.
When clicking on their bed, there was no option for woohoo, however, clicking on the shower and the pool both gave me the option, but when clicking on it, nothing happens.
I also noticed later that in the relationship tab for both of their profiles, it said that they were sisters. But it still said that they were married. And a reminder that these are custom sims that did not come off the gallery.

Today, I saved the game before doing this, but I used UI Cheats to clear the marriage to see what would happen. They were no longer married, it still said they were sisters and even more annoyingly, I still didn't have any other romance options. I ended up reloading the save from before I did that.

Whatever this glitch is, not only does it not happen in all of my other saves, but one of the daughters is married, has a child, and can still do all romance options with her spouse.

I tagged this with mods, but truthfully, I only have MCCC and UI Cheats, which are both completely updated.