I don't live there any more but I remember a group called Indy Feral that traps, spays and releases cats. If that doesn't work call the Hamilton County Humane Society to ask if they have any programs to assist you. If they don't keep trying. Their are groups out there that can help. Try Facebook as well. Save a Stray is one of them. Hope that helps!
Humane has low cost vet
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