My question regards the Abdullah ibn Jaafar, the husband of Zainab. I have read that he wasn’t able to be with Imam Hussain at Karbala and have read he threw a sandal at a companion regarding something he said about the Imam. My question is: what was the reason Abdullah ibn Jaafar wasn’t present at Karbala?

Some historians say that the reason for Abdullah Ibin Jafar not to leave Madina with Imam Hussain (PBUH) was that he had lost his sight due to a illness.
Others say he was asked by Imam Hussain (PBUH) to stay in Madina for the safety of the rest of the Hashimies (Bani Hashim) who were in Madina.
And some say he couldn't travel with Imam Hussain due to his old age .