Hudhaifa bin 'Utba bin Rabî'a bin 'Abdi-Shams who had witnessed the battle of Badr along with the Prophet (ﷺ) adopted Sâlim as his son, to whom he married his niece Hind bint Al-Walid bin Utba bin Rabî'a; and Sâlim was the freed slave of an woman, just as the Prophet (ﷺ) had adopted Zaid as his son. It was the custom in the Period of Ignorance that if somebody adopted a boy, the people would call him the son of the adoptive father and he would be the latter's heir. But when Allâh revealed the Divine Verse:- "Call them (adopted sons) by (the names of) their fathers.... your freed-slaves ' (V.33:5). The adopted persons were called by their fathers ' names. The one whose father was not known, would be regarded as a Maula and your brother in religion. Later on Sahla bint Suhail bin 'Amr Al-Qurashî Al-'Aamrî and-she was the wife of Hudhaifa bin ' Utba came to the Prophet (ﷺ) -- and said, "O Allâh's Messenger (ﷺ)! We used to consider Sâlim as our (adopted) son, and now Allâh has revealed what you know (regarding adopted sons)." (The subnarrator) then mentioned the rest of the narration. [7:25-O.B]