That ʿAisha the wife of the Prophet ﷺ told her uncle that once, while the Prophet ﷺ was in her house, she heard a man asking Hafsa's permission to enter her house. ʿAisha said, "I said, 'O Messenger of Allah ﷺ! I think the man is Hafsa's foster uncle.' " ʿAisha added, "O Messenger of Allah ﷺ! There is a man asking the permission to enter your house." Messenger of Allah ﷺ replied, "I think the man is Hafsa's foster uncle." ʿAisha said, "If so-and-so were living (i.e. her foster uncle) would he be allowed to visit me?" Allah's Apostle said, "Yes, he would, as the foster relations are treated like blood relations (in marital affairs).  

أَنَّ عَائِشَةَ ؓ زَوْجَ النَّبِيِّ ﷺ أَخْبَرَتْهَا أَنَّ رَسُولَ اللَّهِ ﷺ كَانَ عِنْدَهَا وَأَنَّهَا سَمِعَتْ صَوْتَ رَجُلٍ يَسْتَأْذِنُ فِي بَيْتِ حَفْصَةَ قَالَتْ عَائِشَةُ فَقُلْتُ يَا رَسُولَ اللَّهِ أُرَاهُ فُلاَنًا لِعَمِّ حَفْصَةَ مِنَ الرَّضَاعَةِ فَقَالَتْ عَائِشَةُ يَا رَسُولَ اللَّهِ هَذَا رَجُلٌ يَسْتَأْذِنُ فِي بَيْتِكَ قَالَتْ فَقَالَ رَسُولُ اللَّهِ ﷺ أُرَاهُ فُلاَنًا لِعَمِّ حَفْصَةَ مِنَ الرَّضَاعَةِ فَقَالَتْ عَائِشَةُ لَوْ كَانَ فُلاَنٌ حَيًّا لِعَمِّهَا مِنَ الرَّضَاعَةِ دَخَلَ عَلَىَّ فَقَالَ رَسُولُ اللَّهِ ﷺ نَعَمْ إِنَّ الرَّضَاعَةَ تُحَرِّمُ مَا يَحْرُمُ مِنَ الْوِلاَدَةِ