silkie can't stand

[babby72]

I found one of my 4 week old bantam silkies in the cage face down I picked it up and she is very much alive and alert but can not stand at all. She will move herself around with her wings to get in a I guess comfortable spot. I can't see any visible signs of injury. She will eat and drink. I don't know what is going on help please

 

[babby72]

The other 3 are fine by the way