Instagram Teen Accounts and parental supervision
The protections switch on by themselves: teen accounts are private, so new followers need approval, notifications go quiet in sleep mode from 10 PM to 7 AM, and a reminder to leave appears after 60 minutes a day. Teens under 16 need a parent's permission to change any of those built-in settings.
Supervision is the useful extra, and it is opt-in on both sides. Once linked, you can see who your teen has messaged in the past seven days but not what was said, which is enough to spot a stranger without reading a single private conversation.
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