The PlayStation 4 lets gamers stream live streams of any game they're playing, including adult games or mature rated games. Kids can view these live streams, and they can comment on them and view other people's comments, even if you have parental controls on.
Also potentially disturbing, The Playroom. It comes pre-loaded on the PS4. Users who own the PlayStation 4's camera can use it to capture video in their own living rooms, and share it across the PlayStation network. And anything goes. Those streams are also available to view, even if your parental controls are cranked up to the maximum limit. You may feel safe if you've disabled the Internet browser in parental controls. But Consumer Reports found that didn't block the live-streamed video either.
Sony's website does provide instructions for blocking the live stream or "user-generated" content. It involves setting up what Sony calls a sub-account for your child. Consumer Reports found that it wasn't a very intuitive process. There are multiple steps, and it isn't very clear.
If you have a PlayStation 4, Consumer Reports has these can find step-by-step instructions to block live-stream content, including The Playroom.