Abu Huraira reported Allah's Messenger (ﷺ) as saying to Hasan
O Allah, behold, I love him. Thou too love him and love one who loves him.
Abu Huraira reported
I went along with Allah's Messenger (ﷺ) at a time during the day but he did not talk to me and I did not talk to him until he reached the market of Bani Qainuqa`. He came back to the tent of Fatima and said: Is the little chap (meaning Hasan) there? We were under the impression that his mother had detained him in order to bathe him and dress him and garland him with a sweet garland. Not much time had passed that he (Hasan) came running until both of them embraced each other, thereupon Allah's Messenger (ﷺ) said: O Allah, I love him; love him Thou and love one who loves him (Hasan).
Al-Bara' b. Azib reported
I saw Hasan b. 'Ali upon the shoulders of Allah's Apostle (ﷺ) and he was saying: O Allah, I love him, and love him Thou.
Al-Bara' b. Azib reported
I saw the Messenger of Allah (ﷺ) with Al-Hasan b. 'Ali placed upon his shoulders and he was saying: O Allah, I love him, and love him Thou.
Iyas reported on the authority of his father
I (had the honour of) leading the white mule on which rode Allah's Apostle (ﷺ) and with him were Hasan and Husain, till it reached the apartment of Allah's Apostle (ﷺ). The one amongst them was seated before him and the other one was seated behind him.