بسم الله الرحمن الرحيم

الجواب حامداومصليا

It is Haram as she is your niece.

حُرِّمَتۡ عَلَيۡڪُمۡ أُمَّهَـٰتُكُمۡ وَبَنَاتُكُمۡ وَأَخَوَٲتُڪُمۡ وَعَمَّـٰتُكُمۡ وَخَـٰلَـٰتُكُمۡ وَبَنَاتُ ٱلۡأَخِ وَبَنَاتُ ٱلۡأُخۡتِ وَأُمَّهَـٰتُڪُمُ ٱلَّـٰتِىٓ أَرۡضَعۡنَكُمۡ وَأَخَوَٲتُڪُم مِّنَ ٱلرَّضَـٰعَةِ وَأُمَّهَـٰتُ نِسَآٮِٕكُمۡ وَرَبَـٰٓٮِٕبُڪُمُ ٱلَّـٰتِى فِى حُجُورِڪُم مِّن نِّسَآٮِٕكُمُ ٱلَّـٰتِى دَخَلۡتُم بِهِنَّ فَإِن لَّمۡ تَكُونُواْ دَخَلۡتُم بِهِنَّ فَلَا جُنَاحَ عَلَيۡڪُمۡ وَحَلَـٰٓٮِٕلُ أَبۡنَآٮِٕڪُمُ ٱلَّذِينَ مِنۡ أَصۡلَـٰبِڪُمۡ وَأَن تَجۡمَعُواْ بَيۡنَ ٱلۡأُخۡتَيۡنِ إِلَّا مَا قَدۡ سَلَفَ‌ۗ إِنَّ ٱللَّهَ كَانَ غَفُورً۬ا رَّحِيمً۬ا

Forbidden 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 foster mother who gave you suck, your foster milk suckling sisters, your wives' mothers, your step daughters under your guardianship, born of your wives to whom you have gone in - but there is no sin on you if you have not gone in them (to marry their daughters), - the wives of your sons who (spring) from your own loins, and two sisters in wedlock at the same time, except for what has already passed; verily, Allâh is Oft¬Forgiving, Most Merciful. (4:23)

And Allah knows best .

13 Shaban 1443/ 17 March 2022