Newbie to my own chickens looking for info

[sdebolt76]

I recently purchased two Delaware hens...one appeared to be an adolescent and the other an adult hen. I got them at night and quickly noticed the younger just didn't seem right. Silly i am sure but didn't seem as active and eyes were not as bright as the others. Day two she laid a soft egg, then nothing day 8 she died. Any ideas? She had good feathers ate well? These are my first chickens so just curious.

 

[Toast n Jelly]

Best to find out from where you got them what the conditions were before coming to live with you. Could be that they weren't taken care of properly (fed, watered). Could also be malformed reproduction system, inbred genetics...etc. or just a weak chick.