Rattles are instruments of ritual used to put the participant in the correct state of mind for the ceremony. They also have a history of being toys given to infants, also to put them in the correct state of mind, i.e. quite.
The rattle babies seem to scream quietly, until shaken. They are a combination of our animal and human selves. As is the tradition in composite creatures they are given aspects of the animal they are combined with, sort of a shadow self and or an animal guide. I also feel compelled to give them the tools they may need to survive. A baby human, bird or deer all need protection and camouflage. A hawk needs the rabbit, a fish the sea. Batboy instead carries the weight of our fear of our animal selves in his little body. He carries the burden of the love/hate relationship we have with this myth of the super hero/monster. A human who carries too much animal, the unwelcome aspects (the wolf-the bat) becomes either a hero or quickly an evil creature to be avoided or stamped out. But as a baby we feel connected somehow to this animal and thereby to ourselves. I know some may look and see only the strangeness of it all but I’m hoping for a small recognition of the self.