Muwatta Malik, Book 17, Hadith 13 (USC-MSA)

Yahya related to me from Malik from Abd ar-Rahman ibn al-Qasim that his father said, ''A'isha used to look after me and one of my brothers - we were orphans - in her house, and she would take the zakat from our property."

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ الْقَاسِمِ، عَنْ أَبِيهِ، أَنَّهُ قَالَ كَانَتْ عَائِشَةُ تَلِينِي وَأَخًا لِي يَتِيمَيْنِ فِي حَجْرِهَا فَكَانَتْ تُخْرِجُ مِنْ أَمْوَالِنَا الزَّكَاةَ ‏.‏

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also referenced under: Book 17, Hadith 593 (In-Book)