The Messenger of Allah (ﷺ) used to pray thirteen rak'ahs, observing six rak'ahs in pairs including the two rak'ahs of dawn prayer. He would observe witr and five rak'ahs. He sat only in the last of them.

The Prophet (ﷺ) used to pray thirteen rak'ahs during the night including the two rak'ahs of the dawn prayer.

The Messenger of Allah (ﷺ) offered the night prayer and then prayed eight rak'ahs standing, and two rak'ahs between the two adhans (i.e. the adhan for the dawn prayer and the iqamah). He never left them.

Jaf'ar b. Musafir said in his version: (He prayed) the two rak'ahs sitting between the two adhans. He added the word sitting.

How many rak'ahs would the Messenger of Allah (ﷺ) pray observing the witr ? She said: He used to observe the witr with four and three, six and three, eight and three, and ten and three rak'ahs never observing less than seven or more than thirteen.

The narrator Ahmad added in his version: He would not observe the witr with two rak'ahs before the dawn. I asked: With what would he observe the witr ? She said: He would never leave it. The version of Ahmad does not mention the words six and three (rak'ahs).

Al-Aswad ibn Yazid said that he entered upon Aisha and asked her about the prayer of the Messenger of Allah (ﷺ) during the night. She said: He used to pray thirteen rak'ahs during the night. Then he began to pray eleven rak'ahs and left two rak'ahs. When he died, he would pray nine rak'ahs during the night. His last prayer during the night was witr.

How would the Messenger of Allah (ﷺ) pray during the night ? He replied: I spent a night with him when he was with Maimunah. He slept and awoke when half the night or one-third of it had passed. He stood up and went to a leather bad containing water. He performed ablution and I also performed ablution with him. He then stood up and I also stood at his left side. He made me stand at his right side. He then put his hand upon my head, as he was touching my ear and awakening me. He then prayed two light rak'ahs and recited Surah al-Fatihah in each of them, and uttered the salutation. He then prayed eleven rak'ahs observing the witr and slept. Then Bilal came to him and said: Prayer, Messenger of Allah. He got up and prayed two rak'ahs, and then led the people in the prayer.

I spent a night with my maternal aunt Maymunah. The Prophet (ﷺ) got up to pray at night. He prayed thirteen rak'ahs including two rak'ahs of the dawn prayer. I guessed that he stood in every rak'ah as long as one could recite Surah al-Muzzammil (73).