We had a beautiful white silkie pullet. She was almost 5 months old and had just won a blue ribbon at the county fair. I was so proud of her and I loved that chicken. Yesterday I noticed that she was really lethargic and her head drooped down towards the ground. I didn't think anything of it until just a few hours ago. I picked her up and she started puking up a watery substance. She wouldn't stop puking and hacking. I looked on the internet and I was pretty sure she had sour crop. I then tipped her upside down and rubbed her crop until she began puking up a yellow bile. I know that you aren't supposed to leave the chicken upside down for more than 15 seconds, but she wouldn't stop puking and if I turned her right-side up, she would stop puking, but continue hacking and it seemed like she was choking. This continued for about 10 minutes, until she stretched her neck out, desperately hacking, flapped her wings, and just died! It was so sad and I would like to know why she died- if anyone has any ideas please let me know.