The "whenever" post made me think of this one. "Since I'm twelve years old..." is a statement I'd expect to be made only by a twelve year old who is proclaiming his right to something based on his advanced years! I've noticed that MA natives use the phrase to mean, "since I was 12 years old I've known this man." Has anyone else heard this ? I'm pretty sure I've heard it elsewhere as well.
I certainly have heard it. It's a little fuzzy, but I think it was from New Yorkers.
I'm from the Midwest and I never heard it in English. But it's the right way to say it in several Romance languages, for instance French. I think Spanish too, but I'm not sure.
Depuis quand es tu içi?
Je travaille là depuis deux ans.