family tree glitch has ruined my legacy save

I play rotational legacy saves most of the time, and after crossing my fingers during the update, I thankfully didn't have any problems with the family tree. All spouses were labelled properly, etc. The couple I'm playing now had one child before the update, who appeared normally on the family tree and is listed as the daughter of that couple.

However, after the update, they had another baby, who seemingly brought the entire thing down completely. Now, the spouse who married into my family is listed as being his wife's half-sister? And their new baby is properly labelled as his son, but for the mum, he's only listed as a household member. I've tried clearing their relationships and manually adding the proper relationship bits, but it only lasts a few seconds before they think they're siblings again. Not only is the family tree looking insane, but they can't have any romantic interactions with each other, as they somehow believe they are siblings. Really hoping for a fix for this?

Note: I do use some mods, and I'm fairly certain that because their new baby was born while using Pandasama's childbirth mod, it has something to do with it. But my mods are all up to date, and I check regularly to ensure they're functioning properly. I never had issues like this with the mod prior to the update, and I'm fairly certain it's an EA issue.