We put out chicks into the coop today and most of it is shaded but there is a little bit of sun in one area. 2 of them layed down there to the side, fanned their wings out and appeared to go to sleep. Another walked on them and they got right up but then fanned their wings out again. What is this? Are they just sunning themselves? This is our first flock and I just want to make sure they're not dying or something. they seem to make a lot of happy peep noises when we let them play in the coop so I'd hate to overreact and bring them inside if the behavior is harmless. Thanks!