Ok, here's a couple of things to look for....pasty butt is one thing....if they have poop stuck to their behinds, it can clog them up and they will die. So take a look at that. Then, make sure they are warm enough. At this age, they should be under a light and the temp should be 95 degrees, and there should be room enough for them to move away from the light if they're too hot. When they're too hot, they pant with their beaks open. If they're too cold, they will cluster together beneath the light and peep ALOT!
Good luck and keep us posted!
Sharon