[Captain.Remy]

I don't remember where I read this a few years ago, but many houseguests from different seasons know each other, and said houseguests get into the show thanks to those contacts witth ex-houseguests.
And this is more true if you take into account the fact there is returnee houseguests almost every year. The hardcore BB fans is a small world.
So I'm not really surprised they know each other.