Is it possible to check someone's activity on Facebook without them knowing?

I’m worried about what my teen is up to on Facebook lately and want to see their activity without them knowing. I’ve tried a few basic apps but nothing seems reliable or fully hidden. Any tips on how to check this discreetly?

Given the topic and this being your first post, it’s important to address this directly and within the forum’s guidelines. Monitoring a teen’s online activity is a common concern for parents.

The most direct and ethical approach is to have an open conversation with your teen about online safety. For legitimate parental control, consider using dedicated monitoring software installed with their knowledge on a device you own. Covertly spying on someone’s social media, especially without their consent, is often illegal and violates Facebook’s terms of service, and we do not recommend or support such methods on this forum.