Assalamualaikum ustaz. Is it permissible for step siblings to marry?
Waalaikumussalam wrt. wbt.,
Alhamdulillah, praise and gratitude to Allah SWT for His countless blessings for us all. Praise and salutations to our beloved Prophet Muhammad PBUH, his family, companions, and all those who follow his footsteps until the Final day.
Stepsiblings are those who became siblings due to the marriage of their parents, where their parents have children before marrying each other (not half-siblings). For example, Fatimah married Ahmad and both already have children of their own from a previous marriage. Fatimah’s and Ahmad’s children are step-siblings.
Thus, step-siblings don’t share any mahram bond. The reason is they aren’t from the same father and mother. They are ajnabi with each other. Thus, it is obligated to cover the aurah between them and it is impermissible for them to be together alone.
Islam only prohibits a man to marry the following stated women and others are permissible. Allah SWT states:
حُرِّمَتْ عَلَيْكُمْ أُمَّهَاتُكُمْ وَبَنَاتُكُمْ وَأَخَوَاتُكُمْ وَعَمَّاتُكُمْ وَخَالَاتُكُمْ وَبَنَاتُ الْأَخِ وَبَنَاتُ الْأُخْتِ وَأُمَّهَاتُكُمُ اللَّاتِي أَرْضَعْنَكُمْ وَأَخَوَاتُكُم مِّنَ الرَّضَاعَةِ وَأُمَّهَاتُ نِسَائِكُمْ وَرَبَائِبُكُمُ اللَّاتِي فِي حُجُورِكُم مِّن نِّسَائِكُمُ اللَّاتِي دَخَلْتُم بِهِنَّ فَإِن لَّمْ تَكُونُوا دَخَلْتُم بِهِنَّ فَلَا جُنَاحَ عَلَيْكُمْ وَحَلَائِلُ أَبْنَائِكُمُ الَّذِينَ مِنْ أَصْلَابِكُمْ وَأَن تَجْمَعُوا بَيْنَ الْأُخْتَيْنِ إِلَّا مَا قَدْ سَلَفَ ۗ إِنَّ اللَّـهَ كَانَ غَفُورًا رَّحِيمًا ﴿٢٣﴾ وَالْمُحْصَنَاتُ مِنَ النِّسَاءِ إِلَّا مَا مَلَكَتْ أَيْمَانُكُمْ ۖ كِتَابَ اللَّـهِ عَلَيْكُمْ ۚ وَأُحِلَّ لَكُم مَّا وَرَاءَ ذَٰلِكُمْ أَن تَبْتَغُوا بِأَمْوَالِكُم مُّحْصِنِينَ غَيْرَ مُسَافِحِينَ ۚ فَمَا اسْتَمْتَعْتُم بِهِ مِنْهُنَّ فَآتُوهُنَّ أُجُورَهُنَّ فَرِيضَةً ۚ وَلَا جُنَاحَ عَلَيْكُمْ فِيمَا تَرَاضَيْتُم بِهِ مِن بَعْدِ الْفَرِيضَةِ ۚ إِنَّ اللَّـهَ كَانَ عَلِيمًا حَكِيمًا
“Prohibited to you [for marriage] are your mothers, your daughters, your sisters, your father’s sisters, your mother’s sisters, your brother’s daughters, your sister’s daughters, your [milk] mothers who nursed you, your sisters through nursing, your wives’ mothers, and your step-daughters under your guardianship [born] of your wives unto whom you have gone in. But if you have not gone in unto them, there is no sin upon you. And [also prohibited are] the wives of your sons who are from your [own] loins, and that you take [in marriage] two sisters simultaneously, except for what has already occurred. Indeed, Allah is ever Forgiving and Merciful. And [also prohibited to you are all] married women except those your right hands possess. [This is] the decree of Allah upon you. And lawful to you are [all others] beyond these, [provided] that you seek them [in marriage] with [gifts from] your property, desiring chastity, not unlawful sexual intercourse. So, for whatever you enjoy [of marriage] from them, give them their due compensation as an obligation. And there is no blame upon you for what you mutually agree to beyond the obligation. Indeed, Allah is ever Knowing and Wise.” 
Imam al-Nawawi stated the following when explaining who is “your sisters” in the above verse: “And your sisters (of whom are prohibited on you from marrying) is any woman birthed by your parents or one of your parents.” 
Hence, it is clear that full siblings or half-siblings are mahram in marriage.
Imam al-Nawawi further stated: “The daughter of a stepfather, mother of a stepfather, daughter’s stepchild, mother to son-in-law, mother to the stepmother, is not mahram and daughter of stepmother is not mahram (not from the marriage with his father).” 
Lastly, we state that a daughter of a stepmother isn’t considered prohibited sibling to be married, for each has a different mother and father even when the stepfather and mother are now married and have had intercourse.
Lastly, may Allah SWT grant us all a true understanding in this religion.
 Surah al-Nisa’: 23-24
 See Raudhah al-Talibin, 7/108
 See Raudhah al-Talibin (7/112)
One thought on “#333: Marriage Between Step Siblings”
My son loves my own sisters daughter . I’m a mom for him,then is it halal or haram marriage