´It was narrated from 'Aishah that:` the Prophet (ﷺ) said: "It is not permissible for a woman to mourn for any deceased person for more than three days, except for her husband."
Hadith ReferenceSunan Ibn Majah / The Chapters on Divorce / Hadith: 2085
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:صحيح مسلم