Some bedouins came to the Prophet ﷺ and asked, "Do you kiss your young children?"The people replied, "Yes."The bedouins said, "But by Allah, we do not kiss them."The Prophet ﷺ responded, "What can I do if Allah has stripped mercy from your hearts?"
حدثنا أبو بكر بن أبي شيبة حدثنا أبو أسامة عن هشام بن عروة عن أبيه
قدم ناس من الأعراب على النبي ﷺ فقالوا أتقبلون صبيانكم قالوا نعم فقالوا لكنا والله ما نقبل فقال النبي ﷺ وأملك أن كان الله قد نزع منكم الرحمة
Muslim narrated it in "Fadail," in the chapter on his mercy toward children and his household, and the merit of that, hadith no. 64/2317, from Ibn Abu Shayba with this wording, and Bukhari narrated it in "Adab," in the chapter on mercy toward one's child, kissing him, and embracing him, hadith no. 5998, from Hisham.