When Jacob returns to his wolf state, his thoughts inadvertently inform the pack of Bella's state. This causes fear and anger among the werewolves; they don't know how the child might act since the child is an offspring of a vampire. Sam commands the pack in the double-timbre of the Alpha, to obey his decision to destroy Bella and her unborn child. Jacob, who still loves Bella, disagrees, revolts, assumes his inherited Alpha position and leaves Sam's pack. Seth, then Leah Clearwater, soon join Jacob and the threesome form a pack with Jacob as Alpha. Jacob, Leah and Seth patrol the Cullen territory to forewarn the family of any impending werewolf attack.