The ruling on one who caused the death of her mother by preparing a certain type of herbs

Q: My mother ordered me not to cook a specific type of herbs, adding that if I cooked these herbs, it might cause my death because I am unable to tolerate their smell, knowing that these herbs are permissible and lawful. In fact, after my mother and I had dinner from those herbs, my mother passed away a few hours later. Am I sinful for that? Do I have a hand in her death? Is there a sin upon me for that? Please inform us, may Allah reward you.

A: If the reality is as you described in the question, then you have committed a sin; because that is undutifulness to parents and mistreatment of her, and you have a sin upon you as long as you knew that your mother was harmed by it, and that she advised you and forbade you, so you are a criminal in this act, a disobedient one who severs family ties, and undutiful to your mother. And upon you is the blood money; because this act that you did is considered quasi-intentional killing. And upon you is also the expiation, which is freeing a believing slave. If you are unable to do so, then fast two consecutive months, sixty days, along with repentance to Allah (Glorified and Exalted is He). We ask Allah for us and for you to accept the repentance and to grant success in all good.