Ai

I don't know her friends.
I don't know her favourite colour.
I don't know if she ever had a pet.
I don't know if she prefers trousers or skirts.
I don't know what kind of beer she drinks.
I don't know her favourite movie.
I don't know what kind of music she likes.
I don't know her favourite subject at school.

But I do know
she is my sister.