Mericks? Or just a bad leg?

[Bccblue88]

I got three little Cornish crosses from a local store. I put them straight with a broody hen who has raised other chicks previously. Everything was great at first, but when they were about two weeks old, one of them had her leg go "dead". It is paralyzed and she was using her wings to push herself around.
Rather than giving up on her, I have just been catering to her a bit. She is now able to walk...a little oddly, but still walking. She eats and drinks and is otherwise normal. Is this a common problem? Will she regain that leg? Is it mericks? Just not sure if I should do something special or if I made a mistake by keeping her.

Also, she was vaccinated and on medicated chick start.

 

[Eggcessive]

Meriks usually doesn't show up in a 2 week old, so I would think she hurt it or could be suffering from another problem. I would start her on poutry vitamins in the water or PolyVisol without iron 2-3 drops daily by mouth, since vitamin deficiency can cause leg problems. .Avian encephalomyelitis can cause paralysis in legs of very young chicks, not that this is what she has, but here is a link about it: http://www.thepoultrysite.com/diseaseinfo/9/avian-encephalomyelitis-epidemic-tremors