Mine are like that too. I have 16 in the coop, the 4 big girls like to stay out later of course, just like the teenagers they are! But, by around 8:30-9:00 they are all ready and settled down. When I come to close the pop door, I take a bowl of hot mash with leftovers, stale bread, lots of stuff half eaten by my kids (only stuff that is suitable for chicks I might add) and they have their bedlunch. The big girls are better at free ranging than the little ones, so they have stopped eating it before bed, but the others go nuts! So nice to know they are all safe and sound and no rounding up anymore...that is until my 2 five day old chicks are ready to join them and then it will be mayhem all over again with integration and worrying about them getting eaten or lost, etc, etc!