YOU SAID:
Alexa is my bestie Sofia is my worstie
INTO JAPANESE
アレクサは私のお姉さんですソフィアは私のお姉さんです
BACK INTO ENGLISH
Alexa is my sister Sofia is my sister
INTO JAPANESE
アレクサは私の妹ですソフィアは私の妹です
BACK INTO ENGLISH
Alexa is my sister Sofia is my sister
That didn't even make that much sense in English.