My heart goes out to you and I’ve seen this happen to my friends cat before. If I’m not mistaken, it’s almost exclusively male cats that are affected due to their urethral anatomy and stress tends to cause the onset of the inflammation. It is very life threatening without treatment, but the cat will live a normal healthy life after the surgery otherwise. You did the right thing taking your baby to the vet right away and saved his life, I hope you get the help and support you need to help him with this procedure ❤️

What type of litter do you use with that box?