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كتاب الدعوات
80  
Invocations
(47)
Chapter: To invoke for increase of offspring, along with His Blessings.
(47)
باب الدُّعَاءِ بِكَثْرَةِ الوَلَدِ مَعَ الْبَرَكَةِ
Sahih al-Bukhari 6380, 6381

Narrated Anas:

Um Sulaim said (to the Prophet), "Anas is your servant; so please invoke for Allah's blessings for him." He said "O Allah! Increase his wealth and offspring, and Bless (for him) whatever You give him."

حَدَّثَنَا أَبُو زَيْدٍ، سَعِيدُ بْنُ الرَّبِيعِ حَدَّثَنَا شُعْبَةُ، عَنْ قَتَادَةَ، قَالَ سَمِعْتُ أَنَسًا ـ رضى الله عنه ـ قَالَ قَالَتْ أُمُّ سُلَيْمٍ أَنَسٌ خَادِمُكَ‏.‏ قَالَ ‏ "‏ اللَّهُمَّ أَكْثِرْ مَالَهُ وَوَلَدَهُ، وَبَارِكْ لَهُ فِيمَا أَعْطَيْتَهُ ‏"‏‏.‏
Reference : Sahih al-Bukhari 6380, 6381
In-book reference : Book 80, Hadith 76
USC-MSA web (English) reference : Vol. 8, Book 75, Hadith 390
  (deprecated numbering scheme)