It is narrated from Hazrat Aisha (may Allah be pleased with her) or Hafsa (may Allah be pleased with her), or from both, that the Prophet (peace and blessings of Allah be upon him) said: It is not permissible for a woman who believes in Allah and the Last Day to mourn for anyone who dies for more than three days, except for her husband.
Hadith Referenceمسند احمد / مسند النساء / 25513
Hadith Gradingحکم دارالسلام:حديث صحيح على وهم فى إسناده ومتنه، م: 1490