Smoking?

Holt: "Mom, do you know anyone who blows cigarettes?"
Mom: "Anyone who smokes?"
Holt: "Yeah, anyone who smokes."
Mom: "No, but I did.  My grandmother smoked."
Holt: "She did?  What happened to her?"
Mom: "Well, she smoked a lot of her life and she got really sick from it and she ended up dying b/c of it.  Cigarettes are like poison to your body."
Holt: "That's sad.  Was it Mimi's mom? Was she sad?"
Mom: "Yes, we were all sad.  They didn't know as much about cigarettes back then.  That's why you should never smoke...we know now that they are very bad for you."
He then went on to ask how they are inhaled and where the "smoke" goes when it enters your body.  What's the "fire" at the end of it?  Why do they still have them if they're bad? etc, etc., etc. 

I didn't even know he'd ever really seen a cigarette, other than on the ground.  I certainly didn't know he'd seen it close enough to know about the "fire" at the end.  He said he sees people smoking in their cars a lot, while we are driving.We talked about it for about 20 minutes.
It was an in depth conversation that I was happy to have w/ my little inquisitive man.  I felt like I was in that commercial that says "It's never too early to have the conversation."  I hope it steers him clear.  I hope I answered correctly.  I hope he never smokes!  There are lots of things I hope he never does.  Having kids is hard!  I hope I'm doing a good job!  What will they ask next?