What can be Done if One's Parents passed away Displeased with One?

Q: Janaa'iz-30: How can one make amends if one's parents passed away while with one?

Answer: One may recite the Qur'aan or give Sadaqah and send the rewards For them. One may also seek Allaah's forgiveness for them, settle their debts if they have any or perform Hajj on their behalf if possible. This will please Allaah and such a child will be regarded as one who was good to his parents. A Hadith states that when a person performs Hajj on behalf of his parents, it will be accepted as theirs. They will then receive the good news and the child will be regarded as one who was good to his parents And Allaah knows best what is most correct.

Fatawa Rahimiyyah vol.3