Random Fires - Inconclusive Cause

I saw a recent uptick in this, only to find I had an outbreak of fear of fires. I used to have trouble getting rid of the fear because I rarely got fires. Now there are constant fires, and if I have several adult or teen sims in the household, the fear spreads, sometimes even to people who were the ones who were "confident" for putting out the fire.

The last time this happened was in a household of 5 adults (one of the households I'm shoving my non-married sims into on my rotation save to try to decrease household bloot). Thankfully, two were casters with the reach, so I finally got rid of most of the fears by sending one of the sims with the fear out to the edge of the neighborhood map and then having one of the casters cause a fire on the ground close to said sim so the sim with the fear could put it out. For some reason, this would not work with one of the casters, though (maybe because she set the fire herself and then put it out), and after 3 tries, I just had her take a fear-removing potion.