I seriously found this on a website:
"Rin Kagamine and her twin brother Len, were the second Vocaloids to be created. She is best known for Meltdown, a solo. She is very jealous of Miku's popularity. She prefers to act Tsundere. "
...No idea how recent this is, but seeing stuff like that makes me mad. I know the fan most likely was a new western fan, but seriously, there's a LOT of information out there that tells you they are not real and have no set background. Personally, I think this fan read too much fanfiction.