A Sire is a vampire who embraces, or creates, another vampire by draining all the blood from a human, then forcing the dying victim to drink the vampire's own blood. The Vampire thus created is called a Childe, is one generation high than its sire, and is partially supernaturally bound to obey and revere its Sire.
Until the childe is released from their sire's blood bond and accepted as a full, independent member of their Vampire Clan, the sire is held responsible for their childe's actions (including their mistakes).