One of my DCs wants to go on Facebook but I am a complete beginner with it and so want to get to know how it works and how to keep DCs safe. I've opened an account and have been playing around with it to investigate 
Incidentally, DC is old enough to be on it!
I've looked at the privacy settings and I'm starting to understand it all, but one thing is puzzling me.
If you go on your child's friend list to keep tabs on what they are up to, can the child not just filter what they want you to see? If I'm understanding it correctly, you can make certain areas available to certain people? So when people say that they monitor their DCs accounts by being friends with them, surely that doesn't work as the DCs can just block certain posts from certain people?
Sorry if this is a ridiculous question 
As I said, I am new to all this 