Of course this only happens when the hen is being raised by morons. Morons who wonder aloud about that broody, broody hen but never think about googling "broody hen". If you google "broody hen" it will tell you to "break up" the hen, or discourage her from sitting on an empty nest till she kills herself or you can give her chicks at about 21 days in. We didn't do either of these things, what's the refrain...oh yes, because we're morons and we didn't know any better.
This is a lesson we learned the hard way, unfortunately. That hen was my third corpse of the week and it's starting to remind me of Clue the movie where after the third or fourth candlestick in the library incident everyone starts to get blase about the bodies. Another body, oh gee, how inconvenient! We're actually not sure what to do with them there are so many. How screwed up is that, we're running out of room to hide the bodies! It's not a good problem to have.