All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
The members of the family of a deceased person are not obliged to visit him every seven days, or every ten days, or at any other specific time. They are not obliged to do this neither on a continuous basis nor on a rarely basis. Rather, to believe so, is an innovation which did not exist at the time of the Prophet and his companions . Visiting graves as a way of admonition and a reminder, and supplicating for the dead is permissible as the Prophet said: "I forbade you from visiting the graves, but you may now visit them, for it reminds you of the Hereafter." [Muslim] Of course, the meaning of the narration is that it is desirable but not an obligation.
Furthermore, it is not permissible to celebrate the memory of the dead, neither on the 3rd, 10th, nor any other day, and doing this is an innovation. On this regard please refer to Fatwa 83604. Besides, it is not an obligation to give food in charity on his behalf but it is permissible to do so. A man came to the Prophet and said: "My mother died suddenly and I think that if she were able to speak, she would have given "charity." May I give charity on her behalf? He replied, "Yes! Give charity on her behalf." [Al-Bukhari] Moreover, the members of the family of the dead are not obliged to gather people to read the Quran on his behalf; this is an innovation which the Prophet and his companions did not do.
Allaah Knows best.