You folks are great. Thanks for the thoughtful replies, and sorry it took me awhile to weigh back in.
We have decided, at the very least, to take her to a vet, get her spayed and try to address any other issues she has. She continues to cling to our porch. We continue to feed her, to feel for...
We live on a street in a small Upstate NY city that may best be described as urban Appalachia.
There are feral cat colonies about two blocks away from us, one living under an auto repair shop, the other under a sprawling, ancient state prison.
Our section of the street is a bit more orderly...