We've been giving Chappy these chewables that are supposed to calm her down.
She won't eat them outright, but they are easy to grind up, and so we sprinkle them on her wet food, which she eats.
The chewables do seem to be working. She is less wild and was even briefly a bit of a lap cat today, which is not her style.
She seemed pretty relaxed and not as agitated as usual.
She even napped a tad while I was in with her.
I still don't think I would trust her with Grizzabella or Franki, but I'm glad she is a bit calmer.
I think she probably has anxiety and maybe even needs medication, but we are trying something more natural right now, and fortunately, it seems to be working.