The problem is that it's not just her privacy she's violating, but the privacy of everyone else, including OP, whose photos get shared by said cousin.
When I got back from a trip I took abroad with my family earlier this year, my friends mentioned that they'd seen the photos that "I" had posted to Facebook. Except... I hadn't posted any photos to Facebook. I have a Facebook account, but I deliberately have a very minimal presence on it. What my friends were seeing was the photos that my mother had posted, and which I had been tagged in. My privacy was violated by someone else's inability to understand Facebook's privacy settings.
Ironically, it was your OWN inability to understand Facebook's privacy settings.
Go to Settings -> Click " Timeline and Tagging Settings" -> Edit " Who can add things to my timeline? " section : " Review posts that friends tag you in before they appear on your Timeline?" make " Enabled "
There, you will never be tagged in another photo or post, and you now have a review process for anyone who attempts those things, so you can manually up or down those things.
Keeping people from tagging you is pretty close, though.
Asymptomatic carrier.
An asymptomatic carrier is one who exhibits no symptoms of the illness but is carrier who can infect others. I don't believe that is the right analogy here.
With herd immunity you have a group with a large rate of participation, which effectively immunizes those that haven't been.
Facebook is the opposite in that you may not be "infected" but if everyone around you is "infected" you might as well be, because Facebook will piece together your information based on what your friends make available.
Plague almost starts to sound like a better analogy...
If Facebook didn't exist, people would still show photos to people in other ways. If someone takes your photo they're more than likely going to show it to somebody so I would assume a low level of privacy by default.
I suspect this is not the issue or what the parent means by privacy.
Rather, they probably mean specifically that they don't want their metadata enriched photos being made available, without their explicit knowledge or consent, to Facebook the company (and therefore also indirectly to any number of other companies / advertisers).
If Facebook didn't exist, people certainly wouldn't do that! That's purely an unavoidable side effect of Facebook's current business model.
That does protect you to some level. But throw in machine learning with image processing and simple metadata extraction and while your friends might not see the photo, Facebook can potentially figure out if you're in the photo whether or not you've been tagged, where the photo was taken, what camera the photo was taken with, what mood you're in, who's with you, what clothes you're wearing etc etc. And then they'll sell that data without ever telling you.
I have a bigger issue with that happening than I have issues with friends seeing photos I may not have wanted to posted myself, to be honest.
And how should I do that if I don't have a Facebook account? How do I tell Facebook to not steal my phone number and texts from phones of my friends?
https://newsroom.fb.com/news/2018/03/fact-check-your-call-an...
"Call and text history logging is part of an opt-in feature for people using Messenger or Facebook Lite on Android. ... This feature does not collect the content of your calls or text messages"
Your friend has a copy and can do whatever they want with them, including share them with Facebook, the NSA/FBI/police, their friends, or anyone else they want to.
If you don't want them shared with Facebook, don't give the people who are sharing them with Facebook a copy.
