Mix up a little molasses water for energy with a little bit of electrolytes/vitamins in it if you have any available. I had one that I thought for sure was retarded and I'd have to cull. He'd just stand/sit there in a daze. Wouldn't drink or eat. I had to feed it drops for a few days till it got sorted out. Now it's 12 weeks old, running around, ruling the coop..
Improvement is good, keep doing what you are doing. Make sure your vitamins have the B's in it, and continue giving that also. Toddler vitamins are probably good. We use infant vitamins here often.
Baby chick Died yesterday. She/he Tried so hard but at least theres no more suffering now. For 3 days I tried to help the little guy and I did see an improvement. I'm more than sure it was a respiratory problem with the 2 chicks. Never mind things like this happen. Xx