There is divergence of opinions about the birth date of Sayyeda Zainab (s.a.). Some say it was in Medina 5th of Jamadi Al-Awwal, and others say it was 1st in the month of Shabaan, in the 6th Hijra year.
It was five years after the Muslims had accompanied the Prophet (peace be upon him and his household) and his family in the migration (Hijrah) to Medina, when the Holy Prophet's daughter, Sayyeda Fatima (s.a.), gave birth to a little girl.
When her father, Imam Ali (AS), saw his daughter for the first time Imam Hussain (a.s.), who was then almost three years old, was with him. The boy exclaimed in delight, "O father, Allah has given me a sister."
At those words Imam Ali (a.s.) began to weep, and when Hussain (a.s.) asked why he was crying so, his father answered that he would soon come to know.
Sayyeda Fatima (s.a.) and Imam Ali (a.s.) did not name their child until a few days after her birth, for they awaited the Prophet's return from a journey so that he could propose the name.
When finally the baby girl was brought before him he held her in his lap and kissed her. The Angel Gabriel came to him and conveyed the name that was to be hers, and then he began to weep.
The Prophet (peace be upon him and his household) asked why Gabriel wept and he answered, "O Prophet of Allah. From early on in life this girl will remain entangled in tribulations and trials in this world. First she will weep over your separation (from this world); thereafter she will bemoan the loss of her mother, then her father, and then her brother Hassan. After all this she will be confronted with the trials of the land of Karbala and the tribulations of that lonely desert, as a result of which her hair will turn gray and her back will be bent."
When the members of the family heard this prophecy they all broke down in tears. Imam Hussain (a.s.) now understood why earlier his father had also wept. Then the Prophet (peace be upon him and his household) named her Zainab (s.a.).
One day, when Zainab (s.a.) was about five years old, she had a strange and terrible dream. A violent wind arose in the city and darkened the earth and the sky. The little girl was tossed hither and thither, and suddenly she found herself stuck in the branches of a huge tree. But the wind was so strong that it uprooted the tree. Zainab (s.a.) caught hold of a branch but that broke. In a panic she grabbed two twigs but these top gave way and she was left falling with no support. Then she woke up. When she told her grand father, the Prophet (peace be upon him and his household), about this dream he wept bitterly and said, "O my daughter. That tree is me who is shortly going to leave this world. The branches are your father Ali and your mother Fatima Zahra, and the twigs are your brothers Hassan and Hussain. They will all depart this world before you do, and you will suffer their separation and loss."
She had barely attained the tender age of seven when her beloved mother passed away. Her mother's death had closely followed her cherished grand father's passing away. Some time later Imam Ali (a.s.) married Umm ul-Banin, whose devotion and piety encouraged Zainab (s.a.) in her learning.
Whilst still a young girl she was fully able to care for and be responsible for the running of her father's household. As much as she cared for the comforts and ease of her brothers and sisters, in her own wants she was frugal and unstintingly generous to the poor, homeless and parentless. After her marriage her husband is reported as having said, "Zainab is the best housewife."
From very early on she developed an unbreakable bond of attachment to her brother Imam Hussain (a.s.).
At times when as a baby in her mother's arms she could not be pacified and made to stop crying, she would quieter down upon being held by her brother, and there she would sit quietly gazing at his face.
Before she would pray she used to first cast a glance at the face of her beloved brother.
One day Fatima (s.a.) mentioned the intensity of her daughter's love for Imam Hussain (a.s.) to the Prophet (peace be upon him and his household). He breathed a deep sigh and said with moistened eyes, "My dear child, this child of mine Zainab would be confronted with a thousand and one calamities and face serious hardships in Karbala."
Zainab (s.a.) grew into a fine stature young woman. Of her physical appearance little is known. When the tragedy of Karbala befell her in her mid fifties she was forced to go out uncovered. It was then that some people remarked that she appeared as a "shining sun" and a "piece of the moon".