twins. >> anais was adopted as an infant by a family in france. >> oh, hey, this is my brother matt. >> reporter: her digital detective work intensified and she tracked down of samantha's youtubeabout being adopted. >> you're being ridiculous. you know what? you were adopted. what? i'm just kidding. i've always known that. >> a touch of hesitation, overwhelmed by massive mu kul cu -- mutual curiosity, they set up a time to chat. >> i am about to go on line to facebook and then skype and skype my potential twin sister, which is really crazy. >> reporter: the power of social networking rendering a vast world in an instant, a very strange and intimate place. >> my connection is really bad. >> oh, my god, you're european! >> this is a really weird experience. >> this is so weird. >> i don't want to get my hopes up, but i think somewhere in the pit of my gut, i knew that it was probably true. >> anais. >> from there, a deepening friendship, talking almost daily and culminating in london with their first in-person meeting. >> first things that you said? >> i poked her head. >> to make sure she was real? >> was there a sense of relief that finally you could get that moment out of the