Originally Posted by Paul Braun
Everyone who crosses the US border into Canada is required to have a passport.
That's just not true. You need proof of citizenship if you are a US or Canadian citizen, but it need not be a passport.
But that's a moot point. Going into the US from Canada, everybody needs a passport, or the passport card Art mentions, or a Nexus Pass
, or a secure drivers license
(this is a special, extra-cost license
available in some border states).
I don't know about children. Nor about air or sea travel.