Broody hen and adding fertile eggs?

[Harmoni]

I have a hen that I though was prebroody but she is definitely broody. All day in a nest box and missing cheat feathers. Today was the 2nd day. How long do I have to give her fertilzed eggs? I'm thinking about buying 2 eggs for her to hatch but wondering on the time frame requirements.

 

[LadiesAndJane]

I believe you have a little lee way. You can place some golf balls or room temp. store eggs under her until you get the fertile ones to keep her broody. Hens can stay broody for weeks on end, but better for them not to, as they lose weight during this time and you do not want to drag it out too much.