Just how tiny they are at first and how fast they grow! I just picked up the last (?) Chickie on my list. I have several babies in the Basement Brothel, all different breeds and ages. The oldest are seperated, but the rest ranging from less than 1 week to 2 weeks are all together. My newest, a 3 day old Mille Fleur, is SO much smaller than I thought and I was afraid she's get trampled even tho the others are still very small. So I had to jerry rig a partition in the container and I gave her the youngest, calmest, tho still twice her size chickie for company. Seems to be working. When she gets a little bigger I will try to combine them all again. As it is now, they can see and hear each other, but not get close enough to hurt her. Ho boy! Why do I always get myself into these predicaments. Guess id be bored without having to be the chicken problem solver.