How can one get rid of feelings of guilt regarding an unintentional incident that occurred with one's mother shortly before her death, and what are the ways to honor one's mother after her passing?

You bear no sin for not answering your mother because sleep overcame you, and the pen is lifted from the sleeper until he awakens. As for the pangs of conscience and feelings of guilt, these are from Satan. We advise you to refrain from them, seek refuge in Allah from Satan, and occupy yourself with what benefits you in your religious and worldly affairs, and what benefits your mother after her death, such as supplicating for her and giving charity on her behalf.