I've been putting the 5-6 wk old buff orpington in with the big chicks during the day. That's been going well, but I'm a paranoid chickie momma and have been bringing it in at night. Tonight I went out with a friend and my partner forgot to bring chickie in. I just went to peek at him and saw he wasn't in the brooder, so graabbed a flashlight and headed outside. There he was in the corner of the run right by the door. Laying in the dirt shivering. The other two chickens were roosting in the door of the coop ignoring baby. I brought him, cuddled him a bit and now he's back in the brooder under the heat lamp. Temps at night have been low 50s, and I know I'm just paranoid.