Sahih al-Bukhari 1260
صحيح البخاري#1260SahihNarrated Hafsa bint Seereen:Um 'Atiyya said that they had entwined the hair of the daughter of Allah's Messenger (ﷺ) in three braids. They first undid her hair, washed and then entwined it in three braids
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 23:21