We isolated her 3(? I think) days ago. she has had free run of the chick starter in the brooder. I've also been feeding her a mix of raw oatmeal, yogurt, and boiled egg yolk. In the time she's been isolated she's nearly caught up in size to the other 2 chicks, and become quite attached to my oldest daughter. snickers(the dog who tries to mother them) has provided a sleeping spot a few times, and here was very worried that the chick was on the kitchen stool I think in another few days I'll stick her back in with the others. She has been going outside for play time with them, so she's not a stranger to them.