On PS4 systems, you can adjust parental controls to prevent your child from playing games based on their ESRB* rating. For example, you could restrict access to games that are rated for Teen and Mature audiences, and allow games that are rated for Everyone and Everyone 10+.

*This video shows Entertainment Software Rating Board (ESRB) rating icons that appear on PS4 games sold in the United States and in Canada. For information about ratings system for other regions and how they apply to the Age Level for Games setting on PS4 systems, please refer to this article: https://manuals.playstation.net/document/en/ps4/basic/kidsapp.html#ID192018
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