YOU SAID:

We are going to meet at your sister's house.

INTO JAPANESE

私たちはあなたの妹の家で会うつもりです。

BACK INTO ENGLISH

We are going to see in your sister's House.

INTO JAPANESE

あなたの妹の家に見に行っています。

BACK INTO ENGLISH

I went to your sister's House.

INTO JAPANESE

あなたの妹の家に行きました。

BACK INTO ENGLISH

I went to your sister's House.