أَخْبَرَنَا عُبَيْدُ اللَّهِ بْنُ سَعِيدٍ أَبُو قُدَامَةَ السَّرَخْسِيُّ، قَالَ حَدَّثَنَا يَحْيَى بْنُ سَعِيدٍ، عَنْ سُفْيَانَ، عَنْ مَنْصُورٍ، عَنْ عُمَارَةَ بْنِ عُمَيْرٍ، عَنْ عَمَّتِهِ، عَنْ عَائِشَةَ، قَالَتْ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ إِنَّ أَطْيَبَ مَا أَكَلَ الرَّجُلُ مِنْ كَسْبِهِ وَإِنَّ وَلَدَ الرَّجُلِ مِنْ كَسْبِهِ ‏"‏ ‏.‏

It was narrated that 'Aishah said: "The Messenger of Allah said: "The best (most Pure) food that a man eats is that which he has earned himself, and a man's child (and his child's wealth) is part of his earnings" (Sahih ) Translation Not Available

Book Ref: Sunan An Nisai Book 44 Hadith 4449
Web Ref:  Sunan An Nisai Vol 5 Book 44 Hadith 4454