This used to be a long post about something that happened in the neighborhood, but I have decided to delete it, on the off chance that the subjects of my rant ever did decide to surf around my website. The bottom line is:
1) spay/neuter your pets unless you have an extremely legitimate reason not to.
2) if an animal is sick, get it treated.
3) if an animal is in pain and is untreatably sick, do the right thing and have your vet euthanize it.