I came home from work yesterday and found one of my new babies (about 6wk old) dead in the coop. A small, black silkie. I'm so sad. I think one of the older, bigger chickens must have hurt him. I feel really bad.
Unless you see damage on the chick that died, it could be something else and not an attack. I had my 'runt' chick die at 9 weeks. I think whatever genetic things she had just couldn't sustain her as she got older. I had a dog like that once. As a pup she was fine but as she got bigger her very small percentage of working kidney was not enough to sustain her life.
Sorry for your loss