Ali bin Abu Talib reported,

Ali said, "Messenger of Allah, if a son is born to me after your death, may I name him after you and give him your kunya?"He replied, "Yes."In another wording, the addition reads, "So it was a special permission granted to me."

Azami 14505

Sahih

عن علي قلت

يا رسول الله، إن ولد لي من بعدك ولد، أسميه باسمك وأكنيه بكنيتك؟ قال: نعم. وزاد في لفظ: فكانت رخصة لي.

الأعظمي 14505صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Superior moral conduct
Chapter
Names, kunyas, and titles
Section
Concession to combine them after the death of the Prophet ﷺ
Numbering
Jami al-Kamil 14505 (2nd edition)
Azami 14505