Sayyiduna Sa'd (may Allah be pleased with him) said: When this verse was revealed to the Prophet (peace and blessings be upon him): "Let us call our sons and your sons, our women and your women" [Surah Al Imran: 61], he (peace and blessings be upon him) called Ali, Fatimah, Hasan and Husayn (may Allah be pleased with them) and said: "O Allah, these are my family."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النكاح / 13392