Safiyya bint Abu 'Ubaid reported that she heard Hafsa daughter of Umar (Allah be pleased with them), (and) wife of Allah's Prophet (ﷺ), narrating a hadith like this from Allah's Apostle (ﷺ), and she made this addition:" She should abstain from adorning herself (in case of the death of her husband) for four months and ten days

English translation · Sahih Muslim