How can I atone for Allah Almighty's punishment of my mother for transgressing His bounds so that she does not enter Hellfire and be tormented, given that she bequeathed to disinherit her only son?

Mistreating one's parents is a grave sin, and its sinfulness is even greater concerning the mother. The mother's will to disinherit her son is invalid, and her estate must be divided according to Islamic law, with the male receiving the share of two females, if her only heirs are her daughter and son. To atone for the mother, one should frequently supplicate for her and give charity on her behalf, especially continuous charity (sadaqah (definition) jariyah). The son must make sincere repentance, frequently supplicate for his mother, perform good deeds for her, and maintain ties with her kin.