Quote from Phoebe in The One Where Chandler Can't Remember Which Sister
Monica: Was it Gina? Ross: Which one's Gina? Rachel: The dark, big hair, with airplane earrings. Monica: No, no, no. That's not Gina, that's Dina. Chandler: See? You can't tell which is which either. Mwah! Phoebe: We didn't fool around with any of them. Mwah mwah!