A detailed medical examination would tell if your sister has ever been pregnant or not.
If she says she hasn't got any kids, that should pretty much settle it.
Or get the money together for DNA testing of you and her. That'll tell.
A great aunt because your grandmother's (mother's mother) sister would be your mother's aunt and one generation back would make them a great
Your mother or father would have to adopt them. Answer You can make her a sister of the heart. That's it.
In order to be true, one of them has to be the sister of one of the two married, which is totally illegal.
Paint her a portrait, or draw her.
Mother is the title given to the leader of a religious order - Mother Superior. Also, Mother Teresa was originally a Sister of Loreto, they are given the title Mother (as opposed to Sister) as soon as they make their final vows, so Mother Teresa was known as Mother even as a teaching Sister.
You are Jewish if your mother is Jewish.
Your mother's sister is your aunt.
Your mother's sister is your aunt.
Your mother's sister is your aunt. Your mother's mother is your grandmother.
Your mother's sister is your aunt.
Mother Teresa's sister would take care of her mother then her mother died and after the death of her mother, Mother Teresa's sister had died!
Your dad's sister in law that is your mother's real sister.