Italy is a country in the Southern Europe. Croatia is a country in the South-Eastern Europe (or Central, depending on interpretation). Because of the close geographical proximity, these two could have influenced each other's languages.
Let's look at some sentences in English, Croatian and Italian:
I drink - Ja pijem - Io bevo
You drink - Ti piješ - Tu bevi
Drink! - Pij! - Bevi!
He drinks - On pije - Lui beve
We drink - Mi pijemo - Noi beviamo
You all drink - Vi pijete - Voi bevete
Ja is similar to io. Ti is similar to tu. The ending -i is the same in imperative. Some verbs in 3rd person singular conjugation have the ending -e. Pijemo and beviamo has root+vowel+"mo". Pijete and bevete end with -ete. Vi and voi are similar.
I wonder why this is so. I also wonder why all other Slavic languages have ja similar to Italian io. This is not only limited to Croatian, but all Slavic languages. How did this happen? Are these languages secretly in a mutual etymological branch, for the lack of terminology experience?
I forgot to add something.
Boy - Dečko - Ragazzo
Boys - Dečki - Ragazzi
Girl - Cura - Ragazza
Girls - Cure - Ragazze
The endings of the nouns with gender and number completely match too!