Ideas
https://drive.google.com/drive/folders/1hGf0dELKHQ2DZ_XTDdF44j6KQTaAqFxv?usp=sharing
I would agree this is still an issue. I have seen it in multiple saves lately.
Sims will have a high friendly relationship, not be in a negative mood or have traits that would predispose them to that sort of behavior (mean, evil, hot headed, etc.) yet they have "fight!" as a first choice conversation option (an option when you first click on another sim) or choose to fight another sim autonomously.
My understanding was always that fighting, in general, was meant to be an interaction that was triggered or more likely when sims had a negative relationship, which would make sense given that if they DO fight they almost always end up despising either other no matter how good their relationship was previously.
EA_Cade I see you wanted a save file - here you go. In this save in the played household sim Duke autonomously fought Rory for NO reason whatsoever that I could see. They were not arguing or anything, they had a positive relationship, none of his traits predispose him to fighting. This point in the save is a bit past when that incident happened but hopefully it still helps.