From Sahih Muslim (Hadith 5621):
Sahl b. Sa'd reported that Mundhir b. Aba Usaid was brought to Allah's Messenger (ﷺ) at the time of his birth Allah's. Apostle (ﷺ) placed him on his thigh and Abfi Usaid kept sitting there. Allah's Apostle (ﷺ) had been occupied with something else before him. Abu Usaid commanded his child to be lifted from the lap of Allah's Messenger (ﷺ) and so he was lifted. When Allah's Messenger (ﷺ) had finished the work he said:Where is the child? Abd Usaid said: Allah's Messenger, we took him away. He said: What is his name? He said; Allah's Messenger, it is so and so, whereupon he (the Holy Prophet) said: Nay, his name is Mundhir, and named him Mundhir on that day
Reference: Muslim 5621