Smoke with him.

Like you said, hes gonna do it anyway. How do you know he hasn't done it yet?

When I first started I was dumb, after smokin' at a friends house and finding out my sister smoked I was like "Can I buy pot off you?" rofl...she didn't know I knew she toked, so she denied it.

I bought some weed off her once, got ripped off too.

Be a good sis(?) and hook your brother up. He WILL do it anyway, and it won't be hard for him. I was 12 when I started. Just make sure you give him guidance on do's and dont's. No one ever gave me those and I made an ass of myself sometimes.