Partially agree, there was some weirdo on another hackernews thread that monitors their 17 year old daughter's phone and has no plans to stop until Apple remove the right on the 18th birthday. Crazy. That said I think it would be reasonable to check up on your 13 year old to ensure there is no pedophiles messaging etc.. I'd probably draw the line at 14 after having a open chat about risks, peados, impersonation, social engineering etc