The ruling on a vow to harm one's wife

Question:
He says: Honorable Shaykh, may Allah grant you success. My mother vowed that if so-and-so married so-and-so, she would slaughter a camel. And so-and-so did marry so-and-so? Yes. How did so-and-so marry so-and-so? Or did he marry so-and-so?

Answer:
It is written that so-and-so married so-and-so; he wrote it on her behalf. Her intention was to harm the woman, that her husband would marry another wife, to cause her harm. She wants to harm her. This is not permissible for her. If she made this vow, it is not considered a vow of obedience; it is not a vow of obedience, because she wants to harm her sister, and that her husband would marry another wife over her to distress her. This is not a vow of obedience. She should seek refuge in Allah from Shaytan and seek His forgiveness. Yes. She does not have to pay the expiation for an oath, nor the expiation for an oath. This is the same as you, because she wants to harm her sister.