Vasilli was an "immortal child," an infant turned vampire. Created by Sasha, mother of the Denali coven, Vasilii was kept hidden from the other members of the coven because of the risk he provided. Despite his adorable appearance, his young age and strength combined meant that he could not control his urges and was at risk to expose the vampire existence. He and Sasha were executed by the Volturi during the purge of the immortal children. (Breaking Dawn, pg. 35)
'My super secret recipe for spaghetti. Handed down for generations,' Billy said gravely. Jacob snorted. 'I don't think Ragu's actually been around that long.' - New Moon, Page 149