We received 22 chicks from Ideal on the 3rd of April, all of them have thrived until this morning. One of my standard partridge cochins was standing all by herself this morning looking ill, she is now not quite 3 weeks old. I threw in a small handful of hulled, organic sunflower seeds and a clump of dandilions like I normally do to keep them occupied and she didn't run over like the rest of the flock. Throughout the day I check on them every couple of hours to freshen their water and stuff and she was standing by herself dozing each time, never saw her eat or drink anything. By this evening, she is weak and feels bony to the touch, she can't really keep her eyes open and can't stand for more than a few seconds. I have pine shavings in the brooder and they are on medicated starter, I give them small amounts of yogurt, boiled egg and sunflower seeds everyday. They also get clumps of grass and weeds to play with and eat. I have chick grit available to them, and the brooder is spacious enough that I am confident this is not the result of an injury from another chick, I have never witnessed them picking on each other before and see no physical injuries. Her crop feels empty and there are no droppings stuck to her vent. Twice tonight I used a medicine dropper to give her water and dipped her beak in some yogurt mixed with starter crumbles. She nibbled the food and drank just a little water, and had a very small, VERY runny poop each time I hand fed her, the poop was very runny, it just hung off her bottom until I wiped it. (Sorry to be gross) I am completely new to chickens, haven't had close contact with them since I was a little girl, so I am hoping you all can point something out I am missing. Maybe the clumps of grass and stuff introduced a parasite of some kind? Can I administer DE as a dewormer to chicks this young and if so, what dosage and should they all receive it? I am willing to handfeed and nurse this chick, but am not able to take her to the vet or spend large amounts of money to save her; I am most concerned that the rest of the chickens do not get sick as well. Thanks in advance, I have enjoyed reading this forum not only for it's wealth of information but for the kind spirit of the people posting for months now, and so appreciate any information you can offer.