'Aishah (May Allah be pleased with her) reported:
The Messenger of Allah (ﷺ) would wake up at Fajr time in a state of Janabah; so he would take bath before dawn and observe fasting.[Al-Bukhari and Muslim]. (DE)
App reference (DE): Book 9, Hadith 254 (DE)
Arabic/English book reference (DE): Book 9, Hadith 1244 (DE)