Thank you so much for your empathy, but I have good news:
At 5:30 this morning, the little furball was yowling at the top of his lungs on the front porch for breakfast!
I must admit that I'm rather embarrassed for having posted this--I was going to take it down this morning, but you posted your kind comments before I could get to it.
But I seriously thought we had lost him after not seeing him for nearly a week.
Thank you so much again, and I am so glad I was wrong!