Hadithcore
Mishkat al-Masabih, 4079

Anas told that one morning he took ‘Abdallah b. Abu Talha to God’s messenger for him to chew something and rub his palate with it,* and found him with a branding-iron in his hand branding the camels of the <i>sadaqa</i>. *This was a custom for the purpose of acquiring a blessing for children. (Bukhari and Muslim.)

وَعَن أنس قَالَ: غَدَوْتُ إِلَى رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ بِعَبْدِ اللَّهِ بْنِ أَبِي طَلْحَةَ لِيُحَنِّكَهُ فَوَافَيْتُهُ فِي يَدِهِ الْمِيسَمُ يَسِمُ إِبِلَ الصَّدَقَة

References1 variant
In-Book Reference
Book 20, Hadith 16