"Dreams are a dangerous thing, if mankind is to truly be free of the oppression of gods and foreign powers then we must learn to dream as one.." ~ The Voice
For many years it was rumored the Voice sought a daughter but was unable or unwilling to father his own, thus it was claimed he created The Dreamer as the next best thing: the only female Keeper she nevertheless surpasses most of her brothers in power and is a skilled psychic limited only by her inability to harm a member of the Golden Empire: the Voice is wise enough not to give such a powerful creation free-will and thus she is as fanatically devoted to him as the others.
The Dreamer utilises her powers for the single goal of controlling the thoughts of citizen and enemy alike - this combined with the innumerable other mind-washing technologies in use by the Golden Empire ensures that only the most brave or foolish of men ever dare to defy the will of the Voice.
In the Neo-Voice's new Golden Empire the Dreamer still holds an important role as she can control the thoughts of ordinary citizens and enemies (the Neo-Voice only capable of controlling the actions of Neo-Humans).
With the discovery of Dominion it has been revealed that Voice did indeed have a biological daughter but gave her up at a very early age - the Dreamer was his attempt to make a new daughter and cover up his past "mistake".