I have 3 new baby chicks possibly a few more on the way. I'm letting the broody hen raise them. I have a large enclosed coop and run that the mom and chicks stay in. In the evening I open the coop to let my roo and other 5 hens in to roost in the coop. Let them out in the morning but mom and the little ones stayed closed in. My question is what age do the chicks need to be to be let out to free range with the others?