Can a divorced sister marry his brother?

Can I "divorce" my brother or sister?

Good evening everyone, my brother (25) and I (23) have a complicated question today and hope to find advice here:

Our father would like to get to know his daughter, our sister, 13 years old. This is prevented as hard as possible by our mother and her friend.

The two never really got to know each other, when my sister was 1 year old he stopped trying to get in touch for her well-being, because our mother squeezed us out after the weekends at our father's because of "How does he live?", "Has." he bought expensive things? "," How much money does he earn? "," What does he do? "," Does he have a girlfriend? ", etc. - he wanted to spare our sister this squeezing and let it stay. After he brought in presents for Christmas and her birthday, which our mother sold on Ebay, he let it go ...

Now, 12 years later, we all agree that she is old enough to meet her father. To take it slow, he followed her on Instagram and she accepted that - knowing who he is. She also followed him back and that went on for several weeks, she liked his pictures etc. and we assumed an interest. After a while he took his heart and wrote to her. After a short time it was marked with "read".

Nothing happened for two weeks. Then came an answer whose choice of words did not come from our sister, but from our mother - we actually knew it immediately, because no 13-year-old writes like this and we also know our mother and her writing style. The answer was full of the reproaches and pragmatic memorized phrases that our mother tried to memorize in the past.

Now we have let rest, today I decided to write to my sister on my own and ask - what should happen. Unfortunately, I discovered that our sister was stuck in that brainwashing process and blindly believed in our mother, just as we used to do before we were older and could see our father for ourselves.

Now many would probably say: "Well, if she doesn't want to, just let her." - but unfortunately she doesn't know any better and only knows our mother's stories. As big brothers, we worry that one day she will regret this decision. In addition, we are sure that our mother will come to her with phrases such as "If you have contact with your father, your mobile phone / your riding participation / whatever is gone" and that she will put additional pressure on her.

We are at the end of our Latin. We want them to see each other and our father has the opportunity to put the situation in perspective. Then if she says she doesn't want any contact with him, that's perfectly fine.

We turn to you with our question in the greatest desperation and hopelessness. Please help us, we really don't know what to do next ...

best regards