This is ridiculous. Italians do not hate sicilians and vice versa. I've been in Sicily plenty times in August when mainlanders come down to vacation in Sicily. There is no animosity.
What I have seen, is Sicilians coming over to the US, and sticking with their own kind. And by their own kind, I mean other immigrants, not sicilian-americans.
They don't trust anyone as a rule, though. Not even each other.
If you are Sicilian or have family members who are Sicilian they are not going to say how they don't like you to your face, or when they are in Sicily.
But there are lots of slurs and bad stereotypes that Northern Italians have about Southern Italians calling them a Terrone, claiming that they're uneducated thieves, or farmers who go to the North and just bring crime and steal jobs from people who are from the North.
