6 month old pullet suddenly cannot walk or stand! Need advice!

[Anoure]

I have a 6 month old pullet who suddenly cannot walk or stand and is holding her mouth open in a weird manner (like they do when they are too hot but it is 65 degrees). She can roost and she can flop around a bit but cannot walk or stand up. She is eating and drinking and I have removed her from the rest of the flock. She was vaccinated for Marek's when I received her and 5 others in March as day old chicks. There are no systems in my other chickens which include the 5 of the same age (1 is rooster) and 3 older chickens born March 09 (1.5yrs). They free range regularly, their coop is not dirty but a bit pooped up at the moment. Their food is dry and fresh and their water is fresh daily. We don't use any pesticides on the yard or anywhere. We did spray fruit trees but it was months ago and we kept them away from them until it rained a few times. Could this be botulism? She doesn't seem to have any ticks or mites no lumps or bumps on her legs or feet, no gray eyes or visible problems/symptoms. We found her this way on Tuesday 9/14. We move her to our barn away from the other chickens, she is roosting on the edge of the brooder and eating an drinking and flopping around laying eggs but cannot walk or stand after 4 days.
What should I do? She hasn't gotten any better or worse since Tuesday. She doesn't have any mites or ticks and her feathers aren't coming out easily (I was reading the other threads on symptoms).
I read about the molasses flushes but I have no idea what to do or what equipment to use, I don't have anything on hand either we've never had a sick chicken and the three older ones are our first flock.

 

[chkn]

Some extra nutrients and B vitamins. There was a thread on here awhile back about B vitamins. How's her comb look? Post a picture if you can.

 

[chkn]

Maybe think about gape worm?

 

[Anoure]

OMG, Someone asked about her comb, it is flopped over. We didn't know why, thought there was something odd about it. It has been that way for a couple months. She is the only chicken that has that and she's now the only one who can't walk/stand. Are they related? What is it? What should I do?

 

[Anoure]

I don't know anything about gape worm. What is it? We are new chicken people the older 3 hens are our first at 1.5yrs flock. And we haven't had any diseases or illnesses ever so we have no meds, no experience at all.