Hens go broody when you don’t want them to… and won’t go broody when you do. 
I recently had a bunch of silkies go broodie (duh!). Couldn't stop them. I then realized I lost some to hawks and moved them into a different part of the coop so they only get out when I'm home rather than go out all day with standard hens. They were so confused & shellshocked that they didn't know where to brood! A couple of days later and they started laying again. No broodies (for now). Try it!
