Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
nasai-kubra:5421 – Qutaybah b. Saʿīd > al-Layth > Yazīd b. Abū Ḥabīb > ʿIrāk > ʿUrwah > ʿĀʾishah

Don't observe veil from him for he is Mahram (one with whom marriage cannot be contracted) on account of fosterage as one is Mahram on account of consanguinity. (Using translation from Muslim 1445i)  

الكبرى للنسائي:٥٤٢١ – أَخْبَرَنَا قُتَيْبَةُ بْنُ سَعِيدٍ قَالَ حَدَّثَنَا اللَّيْثُ عَنْ يَزِيدَ بْنِ أَبِي حَبِيبٍ عَنْ عِرَاكٍ عَنْ عُرْوَةَ عَنْ عَائِشَةَ أَنَّهَا أَخْبَرَتْهُ

أَنَّ عَمَّهَا مِنَ الرَّضَاعَةِ يُسَمَّى أَفْلَحَ اسْتَأْذَنَ عَلَيْهَا فَحَجَبَتْهُ فَأَخْبَرَتْ رَسُولَ اللهِ ﷺ فَقَالَ لَهَا «لَا تَحْتَجِبِي مِنْهُ فَإِنَّهُ يَحْرُمُ مِنَ الرَّضَاعِ مَا يَحْرُمُ مِنَ النَّسَبِ»  

See similar narrations below:

Collected by Muslim, Nasāʾī, Bayhaqī
muslim:1445i – [Chain 1] Qutaybah b. Saʿīd > Layth [Chain 2] Muḥammad b. Rumḥ > al-Layth > Yazīd b. Abū Ḥabīb > ʿIrāk > ʿUrwah > ʿĀʾishah

Don't observe veil from him for he is Mahram (one with whom marriage cannot be contracted) on account of fosterage as one is Mahram on account of consanguinity.  

مسلم:١٤٤٥i – حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ حَدَّثَنَا لَيْثٌ ح وَحَدَّثَنَا مُحَمَّدُ بْنُ رُمْحٍ أَخْبَرَنَا اللَّيْثُ عَنْ يَزِيدَ بْنِ أَبِي حَبِيبٍ عَنْ عِرَاكٍ عَنْ عُرْوَةَ عَنْ عَائِشَةَ أَنَّهَا أَخْبَرَتْهُ

أَنَّ عَمَّهَا مِنَ الرَّضَاعَةِ يُسَمَّى أَفْلَحَ اسْتَأْذَنَ عَلَيْهَا فَحَجَبَتْهُ فَأَخْبَرَتْ رَسُولَ اللَّهِ ﷺ فَقَالَ لَهَا لاَ تَحْتَجِبِي مِنْهُ فَإِنَّهُ يَحْرُمُ مِنَ الرَّضَاعَةِ مَا يَحْرُمُ مِنَ النَّسَبِ  

nasai:3301 – Qutaybah > al-Layth > Yazīd b. Abū Ḥabīb > ʿIrāk > ʿUrwah > ʿĀʾishah

"Do not observe Hijab before him, for what becomes unlawful (for marriage) through breast-feeding is that which becomes unlawful through lineage."  

النسائي:٣٣٠١ – أَخْبَرَنَا قُتَيْبَةُ قَالَ حَدَّثَنَا اللَّيْثُ عَنْ يَزِيدَ بْنِ أَبِي حَبِيبٍ عَنْ عِرَاكٍ عَنْ عُرْوَةَ عَنْ عَائِشَةَ أَنَّهَا أَخْبَرَتْهُ

أَنَّ عَمَّهَا مِنَ الرَّضَاعَةِ يُسَمَّى أَفْلَحَ اسْتَأْذَنَ عَلَيْهَا فَحَجَبَتْهُ فَأُخْبِرَ رَسُولُ اللَّهِ ﷺ فَقَالَ لاَ تَحْتَجِبِي مِنْهُ فَإِنَّهُ يَحْرُمُ مِنَ الرَّضَاعِ مَا يَحْرُمُ مِنَ النَّسَبِ  

bayhaqi:15611 – [Chain 1] Abū ʿAbdullāh al-Ḥāfiẓ > Abū al-ʿAbbās Muḥammad b. Yaʿqūb > Baḥr b. Naṣr > ʿAbdullāh b. Wahb > al-Layth [Chain 2] And ʾNbʾ Abū al-Faḍl b. Ibrāhīm > Aḥmad b. Salamah > Qutaybah b. Saʿīd > al-Layth > Yazīd b. Abū Ḥabīb > ʿIrāk b. Mālik > ʿUrwah > ʿĀʾishah

Don't observe veil from him for he is Mahram (one with whom marriage cannot be contracted) on account of fosterage as one is Mahram on account of consanguinity. (Using translation from Muslim 1445i)   

البيهقي:١٥٦١١ – وَأَخْبَرَنَا أَبُو عَبْدِ اللهِ الْحَافِظُ نا أَبُو الْعَبَّاسِ مُحَمَّدُ بْنُ يَعْقُوبَ نا بَحْرُ بْنُ نَصْرٍ نا عَبْدُ اللهِ بْنُ وَهْبٍ أَخْبَرَنِي اللَّيْثُ ح قَالَ وَأنبأ أَبُو الْفَضْلِ بْنُ إِبْرَاهِيمَ وَاللَّفْظُ لَهُ ثنا أَحْمَدُ بْنُ سَلَمَةَ ثنا قُتَيْبَةُ بْنُ سَعِيدٍ ثنا اللَّيْثُ عَنْ يَزِيدَ بْنِ أَبِي حَبِيبٍ عَنْ عِرَاكِ بْنِ مَالِكٍ عَنْ عُرْوَةَ عَنْ عَائِشَةَ ؓ أَنَّهَا أَخْبَرَتْهُ أَنَّ

عَمَّهَا مِنَ الرَّضَاعَةِ يُسَمَّى أَفْلَحُ اسْتَأْذَنَ عَلَيْهَا فَحَجَبَتْهُ فَأَخْبَرَتْ رَسُولَ اللهِ ﷺ فَقَالَ لَهَا لَا تَحْتَجِبِي فَإِنَّهُ يَحْرُمُ مِنَ الرَّضَاعَةِ مَا يَحْرُمُ مِنَ النَّسَبِ  

رَوَاهُ مُسْلِمٌ فِي الصَّحِيحِ عَنْ قُتَيْبَةَ