I'm happy to weigh in on this subject with some thoughts, because it's something I have turned my mind to.
In the legislation, it refers to minors, and minors are defined by provincial law. Minors are 18 in Alberta and Quebec and 19 everywhere else, so there's a different line.
One of the challenges that I think exist with children and privacy is that there really are no easily drawn bright lines that say that under this particular magic age, you are completely under the control of your parents and you have no ability to consent in a valid, true way—