What does the Bloody Child Represent?

        The one to give Macbeth his extreme arrogance and confidence throughout the ending of the story, is the 2nd Apparition, the Bloody Child. This child actually is very interesting for the idea of his design and what he tells. The Bloody Child gives Macbeth a tricky fact that goes along the lines of, "Laugh to scorn the power of man, for none of woman born shall harm Macbeth." Macbeth then goes on another relief and talks about how he has nothing to worry about anymore, and that his fear is gone. As the story goes onto the climax, Macbeth increasingly gets more secretly worried about everything going on around him and still clinging onto his idea that no one can kill him. The problem is, Macduff isn't born of a woman, he was born from a MAN...just kidding, he was born from a dead woman/corpse. Sucks. Long story short, Macduff kills Macbeth. Why did the Bloody Child give Macbeth such a double-edged piece of information though? What does he accomplish with it?
        In a small theory I have about the Bloody Child and his involvement within the story, I think the design and warning give a picture to what it may be. There are two things that might hint towards the theme of the child: First, the child could be imaged to be an evil spirit disguising himself to be innocent, but cannot with all the blood he has spilled. A metaphor for how the piece of information stuck to Macbeth during the story, a reliable piece of information that causes him to spill blood based on the power of the knowledge he was given.
        Two: This is a bit lazy but the bloody child could be a reference to the birth of Macduff himself, born from a dead mother, like the past coming to the future to tell Macbeth himself that warning.

(sorry for the disturbing image but it's close to what I typed down)