The Prophet ﷺ said about Hasan and Husayn, "O Allah, I love them, so love them, and whoever loves them has loved me."
أن النبي ﷺ قال للحسن والحسين: اللهم إني أحبهما فأحببهما، ومن أحبهما فقد أحبني.
Bazzar (1820) narrated it from Yusuf bin Musa, who said, Abu Bakr bin Ayyash told us, from Asim (that is, Ibn Bahdala), from Zayd (that is, Ibn Hubaysh), from Abdullah, and he mentioned it.Haythami mentioned it in al-Majma (9/180) and said, "Bazzar narrated it, and its chain is good." This is as he said, for Asim bin Bahdala is disputed, but his hadith is hasan when he does not contradict others and does not bring something that is rejected of him.