From Inside the Grey House:
He continued the story as she made breakfast. Though she listened, part of her mind was on the fact that Natalia had a human friend. Rebecca knew it was dangerous to have human friends. She had none herself. Never had. She grew up knowing what she would become and had been warned against making any unnecessary bonds. Her only friends growing up were the adult werewolves her parents knew and Vincent’s crew. Her parents worked for Vincent until Rebecca was old enough to take over. Vincent convinced her great-grandfather to work for him, and her family had been working for the vampire ever since.