Can I take my 17 year old friend into Canada?

I'm 19, and my friend is 17. I have an aunt and uncle that live in Toronto and we want to drive to go visit them. We both have passports, but is there a law saying I can't take him across? I don't want to be charged with kidnapping lol. I've read that we'll need a notarized and signed written permission letter from his parents but is there anything else?