From Sahih Muslim (Hadith 2174):
Umm 'Atiyya reported:There came to us the Messenger of Allah (ﷺ) 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
Reference: Muslim 2174