Social media sites sometimes ask you to give what your connection is, but I couldn't find the choice to indicate "I love him" or "he's my brother".
Linkedin recently surprised me by having my stepbrother on a list of people they "suggested" I might have a connection with, and I truly can't imagine how they connected us. I clicked his name and it didn't have a reason for anticipating where we were connected. I have a small group of association colleagues on my list, and he has gigantic list of business school and other colleagues on his. We've never had the same last name, never lived in the same city at the same time, don't have any colleagues connected to each other, not in same industry. But the database gods know it anyway. Just like Facebook knew to connect my personal and professional info when displaying a purchase.
So I indicated we're in a "group" together, since no box for love.
I keep finding that if have a social media site, even with intent just to learn, it's really important to keep checking to see what's evolving with it. And don't start adding people unless you know why you're doing it (there are privacy and display settings worth investigating too - some require proactive steps.)
What's your social media "connections" strategy:
1. As many as you can get (like Tila - what's "popularity")
2. Those you know
3. Those you know and sort of know
4. Never adding name to any social media site