Al-Ahzab - 33:55

لَّا جُنَاحَ عَلَيْهِنَّ فِي آبَائِهِنَّ وَلَا أَبْنَائِهِنَّ وَلَا إِخْوَانِهِنَّ وَلَا أَبْنَاء إِخْوَانِهِنَّ وَلَا أَبْنَاء أَخَوَاتِهِنَّ وَلَا نِسَائِهِنَّ وَلَا مَا مَلَكَتْ أَيْمَانُهُنَّ وَاتَّقِينَ اللَّهَ إِنَّ اللَّهَ كَانَ عَلَى كُلِّ شَيْءٍ شَهِيدًا
[33:55]
There is no blame on them in respect of their fathers, nor their brothers, nor their brothers' sons, nor their sisters' sons nor their own women, nor of what their right hands possess; and be careful of (your duty to) Allah; surely Allah is a witness of all things.
There is no blame (on these ladies if they appear) before their fathers or their sons, their brothers, or their brother's sons, or their sisters' sons, or their women, or the (slaves) whom their right hands possess. And, (ladies), fear Allah; for Allah is Witness to all things.
It is no sin for them (thy wives) to converse freely) with their fathers, or their sons, or their brothers, or their brothers' sons, or the sons of their sisters or of their own women, or their slaves. O women! Keep your duty to Allah. Lo! Allah is ever Witness over all things.