This week, we are looking at how kids use social media and the risks and rules around it. It’s part of our new series “The Infinite Scroll.” Monday, we talked about how habitually checking social media can change adolescents’ brains, making them more sensitive to feedback from their peers. Today, we’re going to look at what it’s like to be a parent monitoring their kids’ social media. One thing’s clear: It can be a lot of work.