Ayesha reported,

We used to prepare the toothstick and water for ablution for the Messenger of Allah ﷺ. Allah would rouse him at whatever hour of the night He willed, and he would clean his teeth, perform ablution, and pray nine units of prayer, not sitting during them except at the eighth. He would praise Allah, send blessings upon His Prophet ﷺ, and supplicate between them, but he would not make the closing salutation. Then he would pray the ninth unit, sit, and mention something similar, praising Allah, sending blessings upon His Prophet ﷺ, and supplicating, then he would make the closing salutation aloud so that we could hear it. After that, he would pray two more units while seated.

أخبرنا هارون بن إسحق عن عبدة عن سعيد عن قتادة عن زرارة بن أوفى عن سعد بن هشام أن

عائشة قالت

كنا نعد لرسول الله ﷺ سواكه وطهوره فيبعثه الله عز وجل لما شاء أن يبعثه من الليل فيستاك ويتوضأ ويصلي تسع ركعات لا يجلس فيهن إلا عند الثامنة ويحمد الله ويصلي على نبيه ﷺ ويدعو بينهن ولا يسلم تسليما ثم يصلي التاسعة ويقعد وذكر كلمة نحوها ويحمد الله ويصلي على نبيه ﷺ ويدعو ثم يسلم تسليما يسمعنا ثم يصلي ركعتين وهو قاعد