tu don't change into a werewolf like humans do when they become vampires. There's supposed to be a certain gene in your family bloodline that decides if tu will be a werewolf o not. If a person has this gene, he needs to reach a certain age before he can have his first change. And his first change can be provoked por strong emotions such as anger, rage, jealousy, hurt, etc. The werewolf-gene is passed down from father to son, father to daughter is also possible but the daughter can not pass down the gene like a son can (I know, UNFAIR!!!!)
Daughters can pass it on too. Otherwise, only the Black, Uley and Ateara families would have werewolf members. The other pack members must have inherited being a werewolf from a maternal line somewhere in their family.
The capability is hereditary. It then gets activated por the presence of a nearby vampire sometime in the werewolf's teens o early twenties. They have a growth spurt, become feverish and their senses get enhanced. Finally, they phase into a lobo for the first time triggered por anger.
