Twin Holy Birthdays: The Birth of the Báb (October 20, 1819) and the Birth of Bahá’u’lláh  (November 12, 1817) occurred on consecutive days according to the Islamic lunar calendar (1 and 2 Muharram, respectively). These Holy Days are celebrated on the first and second days of the eighth lunar month after Naw-Rúz, and may fall as early as October 20-21 and as late as November 11-12. They are two of the nine holy days of the year when work is suspended and children are exempted from attending school.