If a man married a nine-year-old girl and had sexual intercourse with her and then divorced her and after the elapse of her `Iddah (woman's prescribed waiting period after divorce or widowhood), she married another man and gave birth to a girl; will it be permissible for the first husband to marry her daughter?
2- The wife of my half-brother suckled a girl; is it permissible for me to marry this girl?
(Part No. 18; Page No. 217)
it is not permissible for a man to marry the daughter of his wife with whom he had sexual intercourse because she is his step-daughter. Allah (Glorified and Exalted be He) says:
Forbidden to you (for marriage) are: your mothers, your daughters
To His saying:
...your step daughters under your guardianship, born of your wives to whom you have gone in
There is no contradiction to the meaning of Allah's saying (Exalted be He):
...under your guardianship
because this is most common among people.
legal texts indicate that the suckling which prohibits marriage must be five or more in number and must be done during the first two years of the child's life. The meaning of a suckle is that a baby holds the breast and suckles milk then leaves it and moves. When he suckles again, it will be considered as one suckling and so on. If the girl suckled in the same way, she is your foster-niece and it is not permissible for you to marry her due to the saying of Allah (Exalted be He):
Forbidden to you (for marriage) are: your mothers
To His saying:
...your brother’s daughters
The Prophet (peace be upon him) said:
Wet-nursing makes unlawful what consanguinity makes unlawful.
(Part No. 18; Page No. 218) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.