I have a favorelle who went broody and adopted 5 chicks. Four are just shy of five weeks and one is a couple of days younger. They are in a brooder box outside, and have been outside with the mommy the whole time, spending the days on the ground. But today the favorelle started pecking the chicks, and the chicks mostly stayed up in the brooder away from her. This evening instead of settling on them, she pecked them viciously, throwing them around, then when I removed her, she hopped up in her old coop with her old coopmate.
So...Tonight is supposed to be 51, the next two nights 47 and 49, highs in the mid 60's with rain. Will they be ok huddled together in the brooder (a box that is 3x2 and 2 feet high, screened door. I put a cardboard box in and put them under it to keep them warmer tonight.... I'll attach some photos of the brooder and the chicks so you can see how feathered out they are.
First photo is smallest youngest chick, a d'uccle, then a bantam brahma, a bantam cochin, one of the two standard chicks on the former mama, there's also another standard chick but I don't have a photo of her. Last photo shows the brooder box.
I put the curtain down at night. There are windows with hardware wire across from each other at the front. I put the cardboard box at the back of the brooder.