Don’t worry too much, dont think I need to monitor her 24/7. I lost my first chicken last month. I can still see her in her sisters. It only goes up from here, you did all you could. Some chickens are just born with bad insides, for lack of a better word. You can’t change her genes, so what...
Something must have been very wrong for her to pass so suddenly. You did all of the right things. Big hugs :hugs I’m so sorry to hear that. She had the best life possible.