Supplication for the deceased is better than everything, and what is the ruling on praying and fasting on their behalf

Question : Peace be upon you. And upon you be peace. She says: Honorable Shaykh, she fasted the six days of Shawwal, and she fasted the rest of the month of Shawwal, and she said that the reward of this fasting is for her mother. Is that permissible for her?

Answer : It is permissible for her to do so. That is, it is permissible to fast in Shawwal or other months, fasting with the intention of it being for her deceased mother, according to many scholars. Some scholars say it is not valid to fast for the deceased or to pray for them except in what has come in the Shari'ah, which is the obligatory prayer. If someone dies and has fasting owed, his guardian fasts on his behalf.
What I advise this woman, the questioner, and others among our Muslim brothers and sisters is to engage in supplication for the deceased instead of making acts of worship for them. Because the Prophet (peace and blessings be upon him) , and he did not mention prayer for the deceased, nor fasting on their behalf, nor charity on their behalf. Even though the hadith is in the context of deeds that benefit the deceased, the Prophet (peace and blessings be upon him) turned away from that to supplication. Whoever wants to benefit his deceased, let him supplicate for him. Whoever wants to follow the Sunnah in that, let him supplicate for him. Whoever wants to be guided by the guidance of the Prophet (peace and blessings be upon him), let him supplicate for the deceased. Why do we turn away from what the Prophet (peace and blessings be upon him) guided us to, toward what our souls desire? Acts of worship are for the living, and supplication is for the deceased.
And you, O living one, the time will come when you will wish that there were one good deed in your record. Make the good deeds for yourself and make the supplication for your deceased. This is what the pure Sunnah suggests. I ask Allah to guide us.