A few years ago, I had a broody with week old chicks that I'd kept separated for that first week. As soon as I let them out, the mama headed for the door, anxious to take a dust bath. The chicks stood at the edge of the door, unsure what to do. All of a sudden the rooster (who until that point had had no contact with the chicks, but had seen them through the wire fence) was there, babysitting the chicks until mama had finished her dust bath. He kept them all together, moved them away from the door, and stayed right with them. I haven't seen a rooster with chicks in his feathers like yours, though. That's cute!