And forbidden to you are your wives’ daughters (those whom they bring from other husbands) whom you rear, when you have consummated marriage with those wives. And Ibn Abbas (may Allah be pleased with them both) said that the words «دخول» , «مسيس» , and «ماس» all mean intercourse. And the explanation of the statement that the offspring of the wife (such as granddaughters or daughters’ daughters) are also forbidden, because the Prophet (peace be upon him) said to Umm Habibah (may Allah be pleased with her):“Do not present your daughters and sisters to me (for marriage).”So among daughters are included the son’s daughter (granddaughter) and the daughter’s daughter (daughter’s daughter), all of them. And likewise, among daughters-in-law are included the son’s wife (grandson’s wife), and among daughters are included the son’s daughters (granddaughters) and daughters’ daughters (granddaughters through daughters), all are included. And the wife’s daughter is always a stepdaughter, whether she is raised by the husband or by someone else, in every way forbidden. And the Prophet (peace be upon him) gave his stepdaughter (Zaynab, who was the daughter of Abu Salamah) to another person (Nawfal al-Ashja‘i) to be raised, and the Prophet (peace be upon him) called his grandson Hasan (may Allah be pleased with him) his son.

Narrated Um Habiba: I said, "O Allah's Apostle! Do you like to have (my sister) the daughter of Abu Sufyan?" The Prophet said, "What shall I do (with her)?" I said, "Marry her." He said, "Do you like that?" I said, "(Yes), for even now I am not your only wife, so I like that my sister should share you with me." He said, "She is not lawful for me (to marry)." I said, "We have heard that you want to marry." He said, "The daughter of Um Salama?" I said, "Yes." He said, "Even if she were not my stepdaughter, she should be unlawful for me to marry, for Thuwaiba suckled me and her father (Abu Salama). So you should neither present your daughters, nor your sisters, to me."