Is there such a thing? I have three BR's in my flock. About 2.5 weeks old. One of them doesn't seem to be growing. She's(I hope) getting her feathers at about the same rate as her cousins but she's much smaller. I let the temp in the brooder room get down to 64f about a week ago. The rest of the girls seemed to handle it but the small one was on her side just kinda kicking meekly when I went to check on them. I picked her up and warmed her in my hands and since then she's been fine as the room is now 80f at the floor. She seems to spend more time eating than the other birds so maybe she's just not as good at getting the food into herself. It's also shocking how much bigger my Black Sex Link is compared to even the largest BR but I'm really not worried about one that's growing well. She looks like a little crow. I wouldn't cull her, of course, but a bantam BR probably wouldn't make a whole lot of scrambled eggs if you know what I mean.