So, I’ve just gotten around to updating my Facebook contacts again after a few months, and I’ve noticed that several members of my (very large) extended family are on. I’ve added the ones I could find easily, but there are surely many more that I’ve missed. What I could do to find them would be to pick two or three of the cousins I’ve already connected to (not siblings of each other), and make a list of mutual friends they have in common, since that would overwhelmingly be other members of the family. Ideally, I’d also make the list only people whom I myself have not yet friended. But I don’t know how to do this, if it’s even possible. Help?
I think you’re stuck with a manual process. There isn’t a way to build a list within Facebook of other people’s friends. I found an app that exports your own friend list to CSV, but it doesn’t appear to do anything with friends of friends. I’d probably use the manual copy/paste method to build a spreadsheet of my friends and my friends’ friends, then use Excel formulas to look for ones that exist in more than one friends’ list but not mine.
An easier (although less robust) approach is to look at the suggested friends. If you have friends with mutual friends, they’ll probably show up here.
My suggestion would be that you contact one of your cousins and ask them to either suggest* everyone they think you know, or use your plan and ask them to suggest all the friends they have in common with one of the other cousins.
*In case you don’t know, by suggesting a friend, you would get a pop up on your page saying that Cousin A has suggested you be friends with Uncle B, would you like to request him as a friend, or something along those lines. From there, you can pick and chose who you want to request.