Let's show them..
I think that you should learn FIRST the language of the whole Country (Italian) and THEN its dialects.
I love dialects, but they are not indipendent languages.
they formed with the accumulations of lots of different languages, and sicilian is an example of this.
Italy is a formal country only since the 19th century. before that time, it was splitted in lots of little reigns and countries, and each of them spoke their tipycall language, that is the actual dialet of this region.
Sicily has a long story of foreing dominations, such as greeks, spanish, arabians, and all their languages influenced the dialet of the island.
but we can't forget that italian (as a language) was born in the 13th century: from 13th to 19th century, it was spread (of course with lots of difficulties) all over the country and all the literary men knew it and used it in their works of art - and it was like this also for the sicilian poets.
so, lots of italian words, part of italian grammar and construction went into the basic dialet.
with the exception of the language spoken in Sardinia and the old language of Friuli Venezia Giulia, that are proper indipendent romance languages, sicilian is a dialet.
that means that it has a relationship with the language of the Country, that's a relationship of substrate and sostrate.
in fact, since the dialects were spoken till the 19th century and over, lots of dialectal words went into italian and became italian words, known and spoken by every scholarized italian.
so, although sicily is really different from italian, they are related.. I think it would be good learning italian, and then see what difference there are between it and sicilian.
Don't forget the pronunciation! Sicilian has a different vocalism than italian, but both come from latin vocalism, so knowing a little latin would help ^__^
..that we can.