NOT SPLAY Leg - 2 week old chick suddenly struggling to walk, hasn't grown like sisters. What is wrong with her?

[a1cluke]

But my 2 week old Polish chick - suddenly is lethargic and unable to walk. Her legs seem to keep crossing each other. She hasn't grown like the other chicks, fully vaccinated for Coccidiosis and Marek's, but starting a few days ago she just started sitting or laying all the time, even to feed. Yesterday she was so lethargic she could barely raise her head to feed or drink, so we put her in her own box (sisters were getting rough) and she seems to be perking up, eating and drinking on her own but still unable to walk. We attempted to take her to the Vet today, but apparently none of the vets in town see baby chicks. Any advice what I should do?

 

[Chicken Heel]

Sounds like simply a failure to thrive which is not all that uncommon. In nature, only the strong survive. It is sad though.