My mother called me at lunch, and I nearly broke into tears. Dad pulled a 180 overnight. He's back to being very active, argumentative, and all around goober. I love it.
The suspicion is that the lumbar drain that placed in him yesterday removed enough fluid from his head to pull him out of that funk. This still is the best theory, but a couple more are still on the table and need to be verified.
Thanks to all of you jujubeings putting out that energy into the ether.
Holy shit pop, you gave me quite a scare. I'll see you tomorrow.