Is it permissible for a man to marry his son's step-daughter?
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
It is permissible for a man to marry the step-daughter of his father or son, due to the Statement of Allaah Almighty (which means): {And lawful to you are [all others] beyond these.}[Quran 4:24]
The author of Ad-Durr Al-Mukhtaar said, "As for the daughter of the wife of the man's father or son, she is lawful for him (to marry)." Ibn Qudaamah concurs in Al-Kaafi saying, "And also the daughters of women as were married by fathers and sons: they are lawful (for him to marry)."
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