I know they can't really change genders- But I've heard of hens developing rooster features, even growing those hackle and saddle feathers, crowing, and sometimes mounting other hens. (They'll stop laying, but can't actually fertilize a hens egg like a born rooster would be able to.)
But other...
I wasn't sure what category to put this thread in- I don't think this is an emergency at all, she's(?) fine.
But I had a 3 year old buff orpington (Early 4's presently) who was always a good layer up until late last year, she(?) hasn't laid a single egg or shown interest in nesting/laying- I do...