The Wedding of Hazrat Qasim ibn e Hassan asw.
Al-Qasim was married to Imam Husayn ibn Ali asw’s eldest daughter, Sakinah (Fatima al-Kubra) bint Husayn, who was 11 at the time. It is said that Husayn asw made a promise to his brother Hasan asw that he will marry his daughter to his son. Therefore, knowing that he was going to die, he arranged the marriage on night of seventh of Muharram, three days before the day of Ashura to keep his promise. It is quoted in Madinat-ul-Ma'ajiz and Wafiyat Al-Aaimmah,
“Then Imam Husayn asw grasped the hand of Qasim as and entered him into the tent, and called Own and Abbas and told Qasim's mother: "Don't we have for Qasim any new clothes?" She said: No.
Then Imam Husain told his sister Zaynab sa, "Bring me the case. Then took it and opened it and brought Imam Hassan's cloth out of it, and dressed it on Qasim, and wrapped the Amamah of Imam Hasan asw on Qasim's head. And took the hand of that daughter of his who was named for Qasim (to be married to Qasim), then performed her Aqd to him, and emptied the tent from others and put the hand of his daughter in hand of Qasim and he went out himself. #YaHussain