The days of the holiday are counted towards the days of mourning, and the rules enforced during mourning are revoked in order to encourage the celebration of a holiday. If a death occurred during the holiday or unknowingly, mourning commences after the holiday ends. In other situations, if the entirety of shiva has been observed prior to the start of a holiday, the holiday will cancel the observance of sheloshim, signifying the fulfillment of this period of mourning.[1]