He asked for Zainab's hand, and Ali accepted it. Her marriage settlement was equal to that of her mother's. Ali told Ja'far not to prevent Zainab from going on a journey with Husayn, her brother.
Although Zaynab bint Ali's husband was a man of means, she lived a modest life, not a life of luxury. She and her husband were charitable to the needy people. The Arab tribes called Abdullah "the sea or the cloud of munificence".
Abdullah was also noted for his standing with Ali in battles. Ibn Hajar quoted Muhammad as having said that Abdullah was like him in character and had taken him by the right hand and prayed to Allah to extend His mercy over the household of Abdullah bin Ja'far.
The marriage of Zainab did not diminish her strong attachment to her family. Ali also felt a great affection for his daughter and nephew and when he became the Caliph of the Muslims and moved from Medina to Kufa, Zainab and Abdullah joined him. Zainab bore four boys by the names:
- Ali ibn Abdullah
- Mohammad ibn Abdullah - killed at Kerbala.
- Aun ibn Abdullah - killed at Kerbala.
- Abbas ibn Abdullah
and two girls named Umm Kulthum.
Correction,Muhammad, son of Abdullah ibn Ja'far and martyr of Karbala was not the biological son of Zaynab. He was the son of al-Khawsa the other wife of Abdullah bin Ja'far http://home.earthlink.net/~downloadquran/Maqtal_al-Husain.pdf Maqtal al-Husayn page 213 for more references.
there are some sources which claims that Abdullah ib Jafar had another son named Muawiya, thru him he had a grandson named Abdullah hi ibn muawiya who led a subsect of the keysaniyyah.