Sick 3 month old pullet. She can't walk and is acting sleepy. I noticed a few days ago that, one of the pullets I just bought a month ago wasn't out in the run with the others 3. She was asleep under the heat lamp in the coop but, looked fine so, left her alone. The next day she wasn't out again so, I went in and found she can't walk and is really lethargic. Didn't try to get up or run from me so, I knew she was sick. I picked her up and offered her water and medicated chick feed out of my hand and she ate like she was starving but, would fall asleep every few minutes while eating. I checked her all over and she has no lice or mites and her vent and poop looks totally fine. I started feeding her scrambled eggs with probiotics and vitamins with electrolytes a couple days ago. I have also been hand feeding water and medicated chick feed so, she now seems aleart but still can't stand or walk. They have been on medicated feed since I got them. I wormed her and the other 3 she is in with, yesterday morning. (Safeguard - pea size amount on tongue) Today my other pullet in this pen is now acting lethargic but, can still walk fine. These chicks had been vaccinated for Mereck. Any ideas ? What else can I do?