In Blood of Eden, sire refers to the vampire, generally a master vampire now since they are the only vampires that can successfully Turn humans without creating Rabids, that Turned a human. They are connected by blood and this connection offers the general location and state of the other, including their health. Vampires that share a sire also have a similar connection, and are near the equivalent of siblings. In a dictionary definition of the word as a normal term, 'sire' means either a respectful form of address for someone of a high social status or the male parent of an animal.