The Book of Occultation — al-Ṭūsī · Hadith 419 (#Ḥadīth #20)
Chapter 34 | Evidence of the Birth of the Master of the Age
210- وروي أن بعض أخوات أبي الحسن عليه السلام كانت لها جارية ربتها تسمى نرجس،فلما كبرت دخل أبومحمد عليه السلام فنظر إليها فقالت له:أراك يا سيدي تنظر إليها؟ فقال: إني ما نظرت إليها إلا متعجبا. أما إن المولود الكريم على الله تعالى يكون منها. ثم أمرها أن تستأذن أبا الحسن عليه السلام في دفعها إليه ففعلت فأمرها بذلك.
H 210 - It is narrated that a sister of Imam Ali Naqi had a slave girl, whom she had raised, called Narjis. When she grew up, Imam Hasan Askari entered and looked at her. She said to him, “I see, my Master, you are looking at her.” He said: “I did not look at her, but wondering: Lo, the baby that is dignified before Allah will be from her.” Then he ordered her to seek permission of Imam Ali Naqi to offer her to him. She did that and Imam Ali Naqi ordered her to do so.
Gradings are classical jarḥ-wa-taʿdīl, name-matched to a rijāl index (not individually re-verified).