What is the parentage of lady Narjis (the mother of Imam Mahdi)?

What is the parentage of lady Narjis (the mother of Imam Mahdi)?

The mother of Imam Mahdi, as the one giving birth to the last divine savior, must have a highly exalted status of spiritual perfection. Unfortunately, for some reason, especially her being in a suffocating and unbearable climate, our understanding of that noble lady is very limited. Following some Islamic narrations and historical reports, there are some general possibilities of her identity:

1. She was a Roman princess captured in a battle by Muslims;

2. She was a slave girl trained in the house of lady Hakīmah (the aunt of Imam ʿAskarī).

However, according to a well-known saying that is derived from some narrations, she was a slave captured subsequently joined the family of Imam Hassan ʿAskarī. As will be mentioned in the following story, there is no contradiction between these two narrations.
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