Mac is back in the vet clinic today with a tentative diagnosis of pancreatitis. That's what they'd thought it was last week, but then he got the fluid around his lungs, and they weren't sure about it. He began showing symptoms again late yesterday -- vomiting what little he was eating, general lethargy (I'm sorry -- sick as he is, the idea of lethargy in cats makes me chuckle. Cats sleep 20 hours a day. If that's not built-in lethargy, what is?)
Bottom line: they're putting fluids in him and soothing his GI tract, and we'll see how he is tomorrow.
It's very hard to watch animals and very small children be sick because they can't tell you where it hurts or how they feel -- they just lay there and whimper. Breaks my heart. We just want Mac to be well.