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كتاب الدعوات
80  
Invocations
(31)
Chapter: To invoke for Allah's Blessings upon the children
(31)
باب الدُّعَاءِ لِلصِّبْيَانِ بِالْبَرَكَةِ وَمَسْحِ رُءُوسِهِمْ
Sahih al-Bukhari 6355

Narrated `Aisha:

The boys used to be brought to the Prophet (ﷺ) and he used to invoke for Allah's blessing upon them. Once an infant was brought to him and it urinated on his clothes. He asked for water and poured it over the place of the urine and did not wash his clothes.

حَدَّثَنَا عَبْدَانُ، أَخْبَرَنَا عَبْدُ اللَّهِ، أَخْبَرَنَا هِشَامُ بْنُ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ قَالَتْ كَانَ النَّبِيُّ صلى الله عليه وسلم يُؤْتَى بِالصِّبْيَانِ فَيَدْعُو لَهُمْ، فَأُتِيَ بِصَبِيٍّ فَبَالَ عَلَى ثَوْبِهِ، فَدَعَا بِمَاءٍ فَأَتْبَعَهُ إِيَّاهُ، وَلَمْ يَغْسِلْهُ‏.‏
Reference : Sahih al-Bukhari 6355
In-book reference : Book 80, Hadith 52
USC-MSA web (English) reference : Vol. 8, Book 75, Hadith 366
  (deprecated numbering scheme)