Hens go broody when you don’t want them to… and won’t go broody when you do. 
I think I may have a brood hen. My little Gerty has been sitting on her unfertilized eggs for a week! I've taken the eggs and give her a nudge to get out for water and food. She takes a drink, eats a little, and jumps right back in. It seems so unnatural to take her eggs.....but really-they're not fertilized! She wants to keep her egg and the other eggs warm, I guess. What to do??