Al-Lu'lu Wal-Marjan 916 — The Book of Ar-Rada' (Suckling foster relations)

A'isha Narrated from:

While the Prophet ﷺ was with me (in my house) I heard a man asking Hafsa's permission to enter her house. 'Âisha رضى الله عنها said, "I said, O Allâh's Messenger! I think the man is Hafsa's foster uncle." 'Âisha added, "O Allâh's Messenger! There is a man asking the permission to enter your house." Allâh's Messenger ﷺ replied, "I think the man is Hafsa's foster uncle."'Âisha said, "If so-and-so were living (i.e. her foster uncle) would he be allowed to visit me?" Allâh's Messenger ﷺ said, "Yes, he would, as the foster suckling relations are treated like blood relations (in marital affairs)," (i.e. those things which are illegal because of blood relation are to be considered illegal because of the corresponding foster suckling relations).( Sahîh Al-Bukhâri, Hadîth No. 814, Vol. 3 )