Sahih Bukhari
Virtues and Merits of the Prophet (pbuh) and his Companions
Volume: 004 / Book Number: 056 / Hadith Number: 742
Narrated 'Uqba bin Al-Harith:
(Once) Abu Bakr offered the 'Asr prayer and then went out walking and saw Al-Hasan playing with the boys. He lifted him on to his shoulders and said, " Let my parents be sacrificed for your sake! (You) resemble the Prophet and not 'Ali," while 'Ali was smiling.