JD,
Take the little one out early and often. Short trips close to home to start with and work your way up from there. Get your wife comfortable with the idea and go from there. We started with our oldest at 10 months and added kids as they came along. Number 3 was 4 mo. old on her first Q trip - 2 weeks, along with her 2 and 4 year old siblings. In my opinion, kids are easier to take care of in the woods and safer to boot!
Good luck with the wife on getting her on board. Be kind and gentle, but tell her that it will be worth it in the long run.
My three oldest are in their twenties now and they constantly thank us for how we made it a priority to always take a 2 week family canoe trip every year to Quetico. It has made a big difference in their lives.
Send me a PM if you would like to talk or need help on anything.
GeneM