I have 6 chickens that free range. When I turn them out, 5 of them head to the house to look for left over bird seed, and one hen stays at the barn. She wanders in and out of the stalls and just does her own thing. Pretty soon, the roo and the other 4 hens make their way back to the barn, and they all join up as a flock again. Sometimes the one hen travels with the flock as they make a trip to the house, but most of the time she happy to stay at the barn. She acts fine, eats and lays eggs, so what's up? One day she hurt her leg somehow and stayed near the coop as she couldn't keep up with the flock, but other than that, I haven't noticed anything different.