The Messenger of Allah (sal Allahu alaihi wa sallam) said: “It is not lawful for a believer to mourn the death of someone for a period of more than three days.” [Tirmidhi]
Do not observe mourning for more than three days on the death of anyone. It is natural to be grief stricken and to weep on the death of loved ones, yet the period of mourning during which one ceases to perform their normal tasks and functions should not exceed three days. Annual public holidays on death anniversaries and rituals of mourning continuing for centuries have no place in Islam.
On the fourth day after the death of the brother of Zainab bint Jahsh (radi Allahu anha) some ladies visited her to offer condolence. Zainab (radi Allahu anha) applied perfume to her person in the presence of everyone and remarked: “I did not need to use perfume at this time. However, I have done so because I heard the Prophet (sal Allahu alaihi wa sallam) say, ‘It is not lawful for a Muslim lady to observe mourning for more than three days for any relation except her husband.’”