YOU SAID:
Hi my sister is stupid, not the youngest the second youngest.
INTO JAPANESE
こんにちは私の妹は愚か者ではなく、最年少ではなく2番目に若いです。
BACK INTO ENGLISH
Hi My sister is not a fool and is not the youngest and second youngest.
INTO JAPANESE
こんにちは私の妹は愚か者ではないし、最年少でも最年少でもありません。
BACK INTO ENGLISH
Hi My sister is not a fool, neither the youngest nor the youngest.
INTO JAPANESE
こんにちは私の姉は愚か者ではなく、最年少でも最年少でもありません。
BACK INTO ENGLISH
Hi My sister is not a fool and is neither the youngest nor the youngest.
INTO JAPANESE
こんにちは私の妹は馬鹿ではなく、最年少でも最年少でもありません。
BACK INTO ENGLISH
Hi My sister is not an idiot, neither the youngest nor the youngest.
INTO JAPANESE
こんにちは私の妹は馬鹿ではない、最年少も最年少も。
BACK INTO ENGLISH
Hi My sister is not an idiot, the youngest and the youngest.
INTO JAPANESE
こんにちは私の妹は馬鹿、最年少、最年少ではありません。
BACK INTO ENGLISH
Hello my sister is a fool, the youngest, not the youngest.
INTO JAPANESE
こんにちは私の妹は愚か者、最年少ではなく最年少です。
BACK INTO ENGLISH
Hi My sister is a fool, not the youngest but the youngest.
INTO JAPANESE
こんにちは私の姉は愚か者で、最年少ではなく最年少です。
BACK INTO ENGLISH
Hi My sister is a fool, not the youngest but the youngest.
You should move to Japan!