What nice things to say! Thanks so much. I'm just another chicken lover, learning more every year that I have these awesome birds. I can tell you one theory that I have, though. I believe the ones who do go broody on occasion give their reproductive systems a well-deserved break and are less likely to suffer the same fate as my poor departed and ailing hens. None of the ones who have died or who are currently suffering from this have ever gone broody, not one time. Heck, they didn't even stop laying to molt, except maybe two weeks, tops. One of my oldest Buff Orpingtons is still laying almost every day at over three and a half years old--she's been broody twice. Even though broodies can be a pain, especially if you have several at one time, I think it's best that they live the life they were meant to live and raise chicks once or twice. Anyway, that's my harebrained theory, for whatever it's worth.
I'm so sorry about your hens. I know how awful it is. Ivy is still breathing very hard. All the fluid/yolk/infection/whatever in her belly is pressing on her organs and certainly her lungs. Not sure how long she'll last, but we gave her the second shot of penicillin today, in hopes that she'll rally somehow.