I have a mixed flock of breeds and ages ranging from 10 weeks to maybe a year old. Two weeks ago we put the 10 week old chicks (8 weeks at the time) into the big coop in their own cage to get acclimated with the rest of the flock. We let them out last weekend but still kept their cage so they could go back into it. We've been watching them and they all seemed to get along fine. This morning when I went out to fill up the water, I found one of them dead. We cleaned the coop and the run and scraped the floors. This afternoon my husband noticed that one of my 19 week olds didn't seem right and looked like she had thrown up. She's a Delaware so we can see the brown running down her chest. He removed her from the rest and I brought her into the house in a crate with clean bedding and water. I don't know if chicks throw up if they eat something bad but not sure that she'll make it. Our biggest concern is that the rest of the flock (18 total) are going to get sick. Help!