Seemingly the actor has his father to thank for the constant screams of countless tweens:
"It's all a bit of a surprise, the acting and fame. I never did acting in school. My dad was in a restaurant and saw a bunch of pretty girls and decided to go up and ask where they had been. They said they went to this drama club, so he said we'd better go down too! It's the only time he's done something like that. We went down there and I began to work backstage. Then one day I was the only one left to play a leading role. That was the first acting I'd done and yet somehow I got an agent."
So, there you have it; the star of Twilight is thus due to a(n alleged) one-off display of lechery by his dad. Every father should be encouraged to follow suit - you'll never know where it'll lead!