The Prophet Muhammad (SAWA) called Ali, Fatima, Hasan and Husain and did not allow any of his wives to join when he explained who are involved in the Verse of Purification (Tatheer). Umm Salama who was the best of the wives after Khadija narrated that herself.
Saheeh Al-Tirmithi, Hadeeth 3205
Al-Sunnan Al-Kubrabby Al-Bayhaqi , V.2 ; page 150
The Prophet (SAWA) clearly said that : Those mentioned in this verse (of Tatheer) are five: myself, Ali, Fatimah, Hasan and Husain. (Mustadrak Al- Saheehain, by Al-Haakim Al-Nisabori , volume 2, page 480.
'Wassalam.I