Cait Sith said that to Cloud/Aeris when he was pretending to be a fortune teller the first time they visit the Gold Saucer ....

refering to? I guess that Cloud will find Sephiroth, but Aeris will die. OR Cloud will find his lucky shirt, but drop 20 gil in the sewers... I'm not sure

I don't really need to mark spoilers in a Trivia thread do I? I mean, they are rather aboundant, like a Mako Fountain