Narrated 'Ali:
that concerning Al-'Abbas, the Prophet (ﷺ) said to 'Umar: "Indeed, the uncle of a man is the Sinw of his father." And 'Umar had spoken to him concerning his charity. (JA)
English reference (JA): Vol. 1, Book 46, Hadith 3760 (JA)
Arabic reference (JA): Book 49, Hadith 4127 (JA)