How is he doing? Also, I'd give him some type of cooked egg (like scrambled egg) mixed in his feed or given as a "treat" - the protein may help his weakness some. I hope he is doing okay!
I'm a noob myself, but I have a family member who has raised Bantams a long time. He always says that chickens naturally stay away from poisonous plants. So, if she ate it, its extremely unlikely that she'll have some type of bad reaction to it. Also, there are several really informative sites...
Here in Minor Hill! Just got my first chickens today! They came in the mail (which made me ridiculously nervous, and they were all fine). Got 6 beautiful Ayam Cemanis and am totally excited. My step-father-in-law has raised bantams for a long time, but this is the first flock that will be...