I never heard the cousins aspect but I know on NSU campus (this is before I was a Zeta) they use to say what's up blue.
I have also heard a call between the Zetas and the Rhos. Every region has they own thing.
I just wish every one in GLO would recongize that "We are Family." I have all my sisters with me. OOOOO...I got a little carried away.
