It is narrated from Sayyiduna Salman (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever loves al-Hasan and al-Husayn, I love him; and whomever I love, Allah loves him. And whoever hates them both, I hate him; and whomever I hate, Allah hates him."
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 6084