> The idea that the family has become such a secondary consideration in modern society, to the point that this mother is advocating to others mothers about the opportunity to vicariously know your own child via the Internet...

Teenagers have been sneaking around behind their parents' backs, trying to assert their own newfound agency and independence, long before the Internet existed. I'm sure parents in the 1960s worried about their 16 years olds "smoking the reefer" and socializing together in groups, late at night, without adult supervision.

I don't think it's unusual at all for a teenager to consciously make a decision not to share every detail of their personal life with their parents, so it's logical that if you want to know what they're really discussing amongst their peer group, look at their social media profiles.