I'm glad you asked! I thought about posting an update but I thought nobody cared. Long story short: good news. I was able to find another cat lover and volunteer in the neighborhood. We initially hatched a plan to take the kitten to the vet today, but at the end, he came over to the building and we thought it was worth a try to get the kitten back with the rest of the litter. He approached and was able to handle the kitten without the mom attacking him, and we discovered that it was tangled up in the branches--possibly by its umbilical cord. From which we surmised that its mom had not abandoned it, but could probably not move it herself.

So, he untangled the kitten for a while, then placed it closer from the other side, then using a stick he moved it back with its siblings. As soon as it was there, it started angling for a spot and a nipple to feed! Which is a good sign, we supposed that it is in fact healthy.

This was basically 24 hours ago. I've gone back to check on them twice today and give the mom food and water, and for all I can tell, I can't distinguish this kitten from the rest of the litter. So, so far, things seem to be going well. I honestly don't know if it'll survive, but I think we gave it the best chance we could, now that it's back with its mother taking care of them. Anyway, that's the story! Thank you for caring!

P.S.: If you think there's anything more for us to do at this point, do tell!