This is new..

[NinjiChicki]

A few weeks ago we picked up chicks at our local TS, all were doing pretty ok, but then one started just laying around. She act like she can't move her legs, just flops over and lay around. I think it's spraddle legs, but it doesn't add up to what I have read before, it started at least after 2 weeks of age. Again though, never had to deal with something like this before.
She's in high spirits, and eats and drinks whenever possible.. A bit of help here? The more pictures and videos the better too.

 

[Calichicks23]

It could be a B vitamin deficiency. I use Rooster Booster brand B vitamin. You can dose the chick individually and also treat the water for the other chicks as a preventative.

 

[Calichicks23]

http://www.poultrydvm.com/condition/curly-toed-paralysis

 

[NinjiChicki]

http://www.poultrydvm.com/condition/curly-toed-paralysis

All we have at the moment for B vitamins is niacin, I can grab some sort of riboflavin* in the morning. I wouldn't think it could be Marek's since they came from a hatchery and she's the only one with the issue for over a week now?
Edit: or grab some rooster booster*

 

[Calichicks23]

I was worried about Mareks too. I had each one of my silkie chicks from the same breeder ( 4 of them ) go through this spring. It took about 2-3 days for improvement. They went through it almost one after the other. Now I treat all chicks water a couple times a week. Good luck

 

[NinjiChicki]

I was worried about Mareks too. I had each one of my silkie chicks from the same breeder ( 4 of them ) go through this spring. It took about 2-3 days for improvement. They went through it almost one after the other. Now I treat all chicks water a couple times a week. Good luck

Well, looks like you're on to something. We started her on niacin right away last night since that's what we had on hand. Then went out earlier today and started her on some Rooster Booster with B vitamins. I don't know if they really work that fast, but she's actually sitting up now! She hasn't done that in a while. We'll keep it up and post again later.

Thank you for the advice!