YOU SAID:

you're half your size of you are of your brother

INTO JAPANESE

あなたはあなたの半分のサイズです

BACK INTO ENGLISH

You are half your size

INTO JAPANESE

あなたは半分のサイズです

BACK INTO ENGLISH

You are half the size

INTO JAPANESE

あなたは半分のサイズです

BACK INTO ENGLISH

You are half the size