Sahih Muslim Book 4, Hadith Number 2047.

Chapter : Washing of the dead body.

Umm ‘Atiyya reported: There came to us the Messenger of Allah (may peace be upon him) as we were washing one of his daughters. So he said: Wash her (dead body) an odd number of times, five times or more than that, the rest of the Hadith is the same. She (further) said: We braided her hair in three plaits: (two) on the sides of her head and one on her forehead.