I have a 3 year old hen, Viper, and 5 babies who are 9 months old. These are not Viper's chicks and she did not brood or raise them, I did. Viper did not like them when we first put them together, she'd chase them and peck them and always stand near the food because they were too scared of her to go past her and eat. Now they're fine together but... When I let all of them out so they can free range in the yard, Viper comes out but she stands right in front of the door so the babies cannot come out. And when a baby or all the babies makes their way out, Viper herds them back in. She does not want them to come out at all. I'll even carry her all the way across the yard and leave the coop door open so the babies can come out, but as soon as I put Viper down, she immediately runs to the coop to make sure the babies don't come out. She's absolutely fine when I just let her out and leave the babies in, she goes around the yard in her usual chicken business. Whenever I leave the door open she just stands there and keeps them in. Why is she doing this? Does she think she's the mom? Is she trying to keep them safe? Or is she just trying to maintain dominance? Or does she really not like them and this is how she's showing it now? Viper is a Barred Plymouth Rock and she was always a very kind and sweet girl; she was also always at the bottom of the pecking order when I had my two other hens and she was completely content with that.