If she is broody (sounds likely), then she will want to stuff her crop really full once or twice a day, so she gets enough food without being off the nest for long.Okay yes hopefully her crop is just full from food, I wish I had known sooner so I could compare it to how it normally is! Because her sisters is like almost unnoticeable in comparison so now im like did that one not get enough food??
A non-broody hen will eat smaller amounts all day long. She doesn't have much else to do--eat, preen, take a dustbath, eat some more. But the broody hen needs to spend her time on the nest, so she rushes through the eating and mostly skips the rest.
I don't think it's needed, but I also think that a single night in a warmer place should be safe enough. A garage or basement (warmer than chicken coop but cooler than your house) would be better if you have it, instead of all the way to human-comfortable temperature. Yes, of course you could bring in more than one chicken, assuming you've got a safe place to put them.
which is NOT ideal and I wanted to avoid at all costs but I am hoping that after a week or so inside and it warms up a bit I can ease her back out. 