Hadith e Kisah which says that Prophet brought Imam Ali, Hassan, Hussain and Lady Fatima and said “O Allah, they are people of my house and remove from them evil and purify them a perfect purification” is very famous and authentic hadith. This is also in Sahih Muslim narrated by Aisha(wife of the Prophet). We can clearly see in this narrations that the Holy Prophet(pbuh) did not allow Umme Salma(one of the righteous wife of the Prophet) to join them under the cloak. It proves that those Ahlulbayt are the special specific people for whom this verse revealed that Holy Prophet announce “O Allah these are my Ahlulbayt”.
For more details please read our article “Who are the Ahlulbayt”.
Sayyidah Umm Salamah (RA) reported that when thisverse was revealed (O Ahlulbayt Allah wants you to take away the impurity from you). Then the Prophet (SAW) called Hasan, Husayn, Ali and Fatimah in Umme Salma’s house and he put the cloak on them then prayed, “O Allah, they are people of my house and remove from them evil and purify them a perfect purification.” Then Umm Salma (RA) asked “Am I not with them?” The Prophet said, “You are on your place and you are on good”.
Here is another narration
Sayyidah Umm Salamah (RA) reported that the Prophet (SAW) put a cloak over Hasan, Husayn, Ali and Fatimah and prayed, “O Allah, they are people of my house and closes to me. Remove from them evil and purify them a perfect purification.” Umm Salamah (RA) submitted, “I too am with them, O Messenger of Allah!” He said, “Indeed you are on what is good.”