Most likely an injury. One of our baby chicks was born okay but mommy stepped on her and either severely injured the leg or broke it. I could not feel a break. We just wrapped it with the vet wrap stuff - although it was probably something I saved from my gazillion blood tests! - and checked it every few days. Mommy left it alone and worked with her for getting her places like jumping up etc. She if just fine today and can do almost everything anybody else does. She does not favor the leg or anything. My thought was that if you can stabilize it the leg will heal itself. Probably will heal itself without being stabilized. Those little chicks are so resilient. I'm glad you have the baby now - not happy with your neighbor.
that you took in the chick.
