my very first babies come in two wks...how long do the babies stay in the brooder (i will have 12)? is that when they feather out? how do i know when they're feathered enough? why do they go to a grow out pen instead of their coop? is that to keep them from other birds (i will have no others at this point)?, when can i put them in the coop & say 'enjoy'? when do i start letting them out in their run during the day (assuming it's warm)? their coop is very nice digs, but i don't want to put them in there too soon if i'm supposed to be doing something else with them first.