Chicken died after sneezing, walking pigeon-toed, soft distended belly. Ascites? Infectious bronchitis?

[PopoMyers]

Found my 2 y.o. golden comet dead this evening when I went to put the flock up. She was laying upside down, and had released some of her food. Her vent was purple, and belly waterballon like. Head, comb, wattles were purple, but neck was not rigor mortis yet.
She had started sneezing last week, and seemed to get more hoarse sounding. She had also not finished her molt quite yet. Also noticed that she was waddling a bit. Didn't check her then, probably should have. She was out with the flock on free range time, and came for treats. It has been in the high 80 to near mid 90 lately. Couldn't bear to cut her open and buried her. No others are sneezing. Couldn't tell if she was laying, but guessing she had stopped because of her molt.

 

[DobieLover]

My guess would be that being a Golden Comet, she had suffered some sort of major reproductive failure. The sneezing was likely the result of her crop backing up from the internal pressure and her not being able to process food and water and it came back out her nose when she bent down. This is the price these birds pay for the high egg production that was bred into them.
I'm very sorry for your loss.