The only real problem is that he is starting to smoke at such a young age. Personally, I don't think anyone should be smoking that young and allthough its not your doing, you should atleast step in as a responsible brother. I wouldn't be suprised if you're the one influencing him in the first place. I know that I would never smoke with my younger brother (or even smoke in front of him for that matter) until he was older because younger brothers always look up to what the older brothers do, and get under the impression that if you do it, then its allright for them to do it too..

If he doesen't want to smoke again because he is afraid he is going to puke, then I would look at that as a good thing. My advice would be to tell him to wait a few years to smoke again because he is too young.