We recently adopted six chickens who were no longer wanted by their keepers. There were two Barred Rocks, two Rhode Island Reds, and two which we now think are Buff Orpingtons.
When we released the babies into the run beside the adults, one of the Buff Orpingtons would stand at the fence and stare over longingly at the little birds. I thought maybe she just missed the small coop where we had housed her and the other adoptees when they first arrived. Then I saw this scene the other night in the henhouse (the babies and adults are now integrated):
The Buff Orpington hen was laying in a pile of babies. She looked like a mother with all her little ones (now teenagers) nestled in around her. I guess she just felt a mothering instinct and so took naturally to the smallest of our flock. We adopted her and now she's adopting all the babies she can fit around her!