A secretive person is up to some mischief.
More Sicilian Proverbs:
Good manners and not beauty leads to love.Sicilian
There are a hundred owners besides you until the wheat is harvested.
Sicilian
The suffering patient knows more than the expert doctor.
Sicilian
Who sells, goes down; who buys, goes up.
Sicilian
When the dripping continues it succeeds in piercing the hardest stone.
Sicilian
The cowherd who has fodder has bread, and if he doesn't have fodder then he ends up without oxen and without bread.
Sicilian