96 – Anas (may Allah be pleased with him) reported: “The Messenger of Allah ﷺ was asked about a woman who sees in her sleep what a man sees. He said, ‘She must perform a ritual bath (ghusl).’” Agreed upon.
Muslim adds: “Umm Salamah asked, ‘Can that really happen?’ He replied, ‘Yes—so from where would the child’s resemblance come, then?!’ (1)

Vocabulary of the ḥadith
• Yes (naʿam): a response particle that stands in place of an omitted verbal reply. If someone asks, ‘Will you go?’ and you answer, ‘Yes,’ the full meaning is ‘Yes, I will go.’ In the ḥadith the understood reply is: ‘Yes, a woman must perform ghusl if she experiences a nocturnal emission.’
• Resemblance (shabah, pl. ashbāh): likeness or similarity. Al-Miṣbāḥ states: “A man resembles (ashbaha) his father when he shares one of his qualities.”

Lessons derived from the ḥadith
1 – Like men, women can have erotic dreams. If a woman experiences such a dream and discharges fluid, a ritual bath of major purification becomes obligatory.
2 – A child’s resemblance—male or female—to its mother is connected to her sexual fluid, which meets the man’s fluid during intercourse: whichever of the two prevails determines the resemblance. Al-Bukhārī records from Anas that the Prophet ﷺ said: “As for resemblance in the child, if the man’s fluid overtakes the woman’s, the child resembles the father; if hers overtakes his, the child resembles the mother.”
3 – According to physicians, heredity is the transfer of factors that cause similarity among offspring.