I got an email from PRA

They informed me that Isis' sibling, who was adopted 4 weeks before we got Isis, died of FIP and Isis might have been exposed.
This is not the kind of news one wants to hear.

Especially after making an appointment for our vet to give her a once over, and have her vaxxes recorded there. Isis was her wriggly squirming self when I told the vet about the possible exposure to the feline corona virus which can develop into FIP. Some blood was taken (*that's another horror story in itself) after putting her in a "twilight sleep" via 'The Box", because she wriggled too much.

Got a phone call from the vet this morning that the testing lab said there is no way to text for feline corona virus, and that typically a positive FIP test comes from testing the fluid in a distended/swollen abdomen.  And with the way Isis was so bright, squirmy, wriggly, trilling, if she was exposed the same time her sibling was, she would have had symptoms by now. All is well.

*The horror story: while waiting in the vet's waiting room, a nurse comes out, thrusting this limp, head drooped, tongue hanging out, floppy thing that was supposed to be Isis at me. No pet carrier, just the above.

I swear, I stopped breathing for a few minutes. I saw her head rear back, eyes unfocused. I 'curled' her up, and held her firmly.
Turns out there was an emergency in the back, and they had to do a resuscitation. She started coming to, and she had claws out. We got our pet carrier back, and Wing managed to get her back into it, and she recovered from the "Twilight sleep".