Etiquette
33/34. Chapter:
A man being given a kunyah before he has a child
Sunan Ibn Majah
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا وَكِيعٌ، عَنْ شُعْبَةَ، عَنْ أَبِي التَّيَّاحِ، عَنْ أَنَسٍ، قَالَ كَانَ النَّبِيُّ ـ صلى الله عليه وسلم ـ يَأْتِينَا فَيَقُولُ لأَخٍ لِي وَكَانَ صَغِيرًا " يَا أَبَا عُمَيْرٍ " .
It was narrated that Anas said: "The Prophet(ﷺ) used to come to us and say to a brother of mine, who was small: 'O Abu Umair.'".
Reference : Sunan Ibn Majah 3740In-book reference : Book 33, Hadith 84English translation : Vol. 5, Book 33, Hadith 3740