First, what age was the chicken when it seemed to have 'changed sex'?
Second, has the 'hen' ever laid eggs. Is it currently laying eggs?
Does this chicken mount the 'certified' hens?
Third, by what method (if not by egg laying) were the three chickens'
sexes 'determined', earlier?
Fourth, did that chicken recently return from a vacation in Denmark?*
Ray Stanford
"You know my method. It is founded upon the observance of trifles." -- Sherlock Holmes in The Boscombe Valley Mystery
* For you 'youngsters' on the list, Denmark became known for pioneering
in sex-change surgery.