Why Did You Begin Smoking?

I was 12 or 13, my sister 14 or 15
Whenever she went on a date, I was sent along to chaperone
Hey boyfriend would then send me to the snack bar to buy him a pack of smokes and me a milkshake...the idea of course was I didn't come back until the milkshake was gone

Somewhere along the lines the milkshake turned into a pack of smokes for me aswell