Sahih Bukhari Volume 005, Book 058, Hadith Number 251.

Narated By Ibn Umar : Umar bin Al-Khattab fixed a grant of 4000 (Dirhams) for every Early Emigrant (i.e. Muhajir) and fixed a grant of 3500 (Dirhams) only for Ibn 'Umar. Somebody said to 'Umar, "Ibn 'Umar is also one of the Early Emigrants; why do you give him less than four-thousand?" 'Umar replied, "His parents took him with them when they migrated, so he was not like the one who had migrated by himself.

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