Shaddad Abu Ammar reported,

I came in to visit Wathila bin Asqa while a group of people were with him, and they began speaking about Ali. When they got up to leave, he said to me, "Shall I not tell you what I myself saw from the Messenger of Allah ﷺ?"I said, "Yes, please do."He said, I came to Fatimah to ask her about Ali. She said, "He has gone to see the Messenger of Allah ﷺ." So I sat down to wait for him, until the Messenger of Allah ﷺ arrived, and with him were Ali, Hasan, and Husayn ﷺ, each of the two boys held by the hand. He came in and drew Ali and Fatimah close, seating them in front of him, and he placed Hasan and Husayn each on one of his thighs. Then he wrapped his garment, or he said his cloak, around them, and recited this verse, "Allah only desires to remove impurity from you, people of the Household, and to purify you with a thorough purification" [Ahzab 33:33]. Then he said, "Allah, these are the people of my household, and the people of my household are most deserving."

عن شداد أبي عمار قال

دخلت على واثلة بن الأسقع وعنده قوم، فذكروا عليا، فلما قاموا قال لي: ألا أخبرك بما رأيت من رسول الله ﷺ: قلت بلى، قال: أتيت فاطمة رضي الله عنها أسألها عن علي، قالت: توجه إلى رسول الله ﷺ فجلست أنتظره حتى جاء رسول الله ﷺ ومعه علي وحسن وحسين ﷺ، آخذ كل واحد منهما بيده، حتى دخل فأدنى عليا وفاطمة، فأجلسهما بين يديه، وأجلس حسنا وحسينا كل واحد منهما على فخذه، ثم لف عليهم ثوبه، أو قال: كساء، ثم تلا هذه الآية: {إنما يريد الله ليذهب عنكم الرجس أهل البيت ويطهركم تطهيرا}. وقال: اللهم هؤلاء أهل بيتي، وأهل بيتي أحق.