Sahih al-Bukhari, Volume 4, Book 54, Hadith 477 (USC-MSA) ⓘ
Narrated Al-Bara (bin Azib): The Prophet, after the death of his son Ibrahim, said, "There is a wet-nurse for him (i.e. Ibrahim) in Paradise."
حَدَّثَنَا حَجَّاجُ بْنُ مِنْهَالٍ، حَدَّثَنَا شُعْبَةُ، قَالَ عَدِيُّ بْنُ ثَابِتٍ أَخْبَرَنِي قَالَ سَمِعْتُ الْبَرَاءَ ـ رضى الله عنه ـ عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ لَمَّا مَاتَ إِبْرَاهِيمُ قَالَ " إِنَّ لَهُ مُرْضِعًا فِي الْجَنَّةِ " .
also referenced under: Book 59, Hadith 65 (In-Book) & Hadith 3255 (DarusSalam)