Yahya related to me from Malik from Jafar ibn Muhammad that hisfather said, "Fatima, the daughter of the Messenger of Allah, mayAllah bless him and grant him peace, weighed the hair of Hasan,Husayn, Zaynab and Umm Kulthum, and gave away in sadaqa an equivalentweight of silver."
USC-MSA web (English) reference: Book 26, Hadith 2
Arabic reference: Book 26, Hadith 1071