(regarding) the Verse: 'And if you fear that you shall not be able to deal justly with the orphans...' (4.3) It is about the orphan girl who is in the custody of a man who is her guardian, and he intends to marry her because of her wealth, but he treats her badly and does not manage her property fairly and honestly. Such a man should marry women of his liking other than her, two or three or four. 'Prohibited to you (for marriage) are: ...your foster-mothers (who suckled you).' (4.23) Marriage is prohibited between persons having a foster suckling relationship corresponding to a blood relationship which renders marriage unlawful.
Sahih al-Bukhari Book 67, Hadith 36
← Previous Hadith Three principles were established because of Barira: (i) When Banra was manumitted she was given the option (to remain with her slave husband or not). (ii) Allah's Messenger (ﷺ) said "The Wala of the slave) is for the one who manumits (the slave). (iii) When Allah's Messenger (ﷺ) entered (the house), he saw a cooking pot on the fire but he was given bread and meat soup from the soup of the home. The Prophet (ﷺ) said, "Didn't I see the cooking pot (on the fire)?" It was said, "That is the meat given in charity to Barira, and you do not eat the (things given in) charity." The Prophet (ﷺ) said, "It is an object of charity for Barira, and it is a present for us."

Sahih al-Bukhari Book 67, Hadith 35 Next Hadith → (the wife of the Prophet) that while Allah's Messenger (ﷺ) was with her, she heard a voice of a man asking permission to enter the house of Hafsa. `Aisha added: I said, "O Allah's Messenger (ﷺ)! This man is asking permission to enter your house." The Prophet (ﷺ) said, "I think he is so-and-so," naming the foster-uncle of Hafsa. `Aisha said, "If so-and-so," naming her foster uncle, "were living, could he enter upon me?" The Prophet (ﷺ) said, "Yes, for foster suckling relations make all those things unlawful which are unlawful through corresponding birth (blood) relations."

Sahih al-Bukhari Book 67, Hadith 37