Nineteenth Ramadan is the day the Imám Ḥusayn was wounded on the battlefield of Karbilá, and the twenty-first, which commemorates his death!

The fifteenth day of the month of Sha‘bán is believed to be the birthday of the Twelfth and Hidden Imám, who, according to, the teachings of Shí‘ah Islam, was the last in the series of successors to the Prophet Muḥammad. There are two holy days during Ramaḍán, the Muslim month of fasting-the nineteenth, which commemorates the day the Imám Ḥusayn was wounded on the battlefield of Karbilá, and the twenty-first, which commemorates his death.

https://bahai-library.com/uhj_messages_1963-86_full&chapter=all/