First of all, thank you so much for all of your great advice for my mom. Star is slowly improving, but it will take some time. Mom said, "Last night Star sat in my lap, looked me square in the eyes, and meowed in a soft voice. I answered (ohhh, I know, poor kitty...) and he repeated his plaintive meowing for about ten minutes. Then he jumped down and went to sleep. He seems calmer so far this morning, but I am reading up on some of your readers' suggested remedies."
Earlier today I got the great news that Melly has kicked the Coccidia! Of course this is very exciting, but unfortunately she still has diarrhea. I picked up some FortiFlora from the vet (also found out they read the blog - hi, Met Vet folks!) on my way home from work, which will hopefully remedy Melly's digestive issues.
The joys of teething.
My Feliway diffuser arrived from Amazon yesterday and I've had it plugged in the kitchen. I haven't noticed much of a difference in cat behavior, but I'm not surprised - these two are constantly fluctuating between ignoring each other, pouncing on each other, and nuzzling each other. (That last one is admittedly pretty rare.) I am going to move the diffuser to the living room, where the majority of the pouncing takes place, and see if it helps there.