I have 11, 3 week old silkies in a brooder. All seem to be doing fine except for this one. It seems to be having constant tremors or ticks. It eats and drinks fine, and it runs around with the other chicks. I've never seen something like this before. It's mainly in the head and neck. It will tilt it's head from side to side constantly. It almost reminds me of parkinsons type of symptoms. I'm wondering if this chick can possibly have a normal life apart from this. But I still have no idea what it could be.