Yes need passport.
Canadian law requires that all persons entering Canada carry proof of citizenship and identity. A passport is usually the best as it's internationally recognized, but a birth certificate and government issued photo ID should suffice. Enjoy your visit!
If you are crossing the border into Canada, yes you all need passports
If you have a USA passport then I guess you can enter Canada but yes you would have to show the passport at the border. I'm not very sure though. I would suggest you call CIC. They will help you with the questions you have.
I would advise you to contact the authority and follow their instructions Instead from this forum.
In any case passport is mandatory
Thanks! Your answer is awaiting moderation.