Hadith.4505 - Muhammad ibn Yahya al-Khazzaz narrated from Ghiyath ibn Ibrahim, from Imam Jafar ibn Muhammad Al-Sadiq (as) from his father, Imam Muhammad ibn Ali Al-Baqir (as), who said
"Imam Ali ibn Abi Talib (as) said: "A woman touching her daughter in an inappropriate manner once she has reached six years of age is a form of indecency (a branch of fornication)."