You must see the problem with the definition. It would qualify children of a whole lot of people who want to do us harm as "natural born citizens" and they wouldn't even have to be born in the USA.
Even the birthers made as their big deal the contention that Obama was born in Kenya. Yet nobody disputed that would've been prohibitive. Instead those defending Obama's eligibility went over the top (some say) to prove Obama was born in the USA.
Some thug pulls a gun on you as you get out of your car in a dark parking lot some night and I am certain that the very first thought that runs through your mind is that maybe this guy is a US citizen - but maybe he was born in Nova Scotia.
Are you for real?
With what you have stated to me in your reply, that would make her child a US citizen at birth, because she can bestow citizenship on her child as a birth mother and that child would be eligible to be president of the USA the same as I am and you are if you are born by a US citizen mother. Location of that mother only maters if she is not there legally.
Brcause the child was born in Canada, the Canadian government would make him or she to be a Canadian citizen, thus creating dual citizenship for the child if their laws still function as they did in 1970.