Brooding in upper box

[Jilara]

I just substituted fertile eggs (showgirls, yay!) for the regular eggs under my broody hen. But I have a concern. She's brooding in the raised nest box, basically a covered cat box I've adapted, and has refused to be moved to something lower. Should I be concerned when the chicks start hatching? I worry about babies falling from there. It's about 18 inches up.

 

[SallyF]

For the first couple of days I leave mine in with the hen and just put food & water in there. The hen doesn't let them get too far and they're more interested in staying warm under mama. When hatching is done, I move everybody to a separate box/pen arrangement (which is self-contained) so the chicks can get around and the hen can get up & walk around also.