Aisha was asked about the night prayer of the Messenger of Allah ﷺ. She replied, "He would pray for a long part of the night standing and for a long part of the night sitting. When he recited standing, he would bow from a standing position, and when he recited sitting, he would bow from a sitting position."
حدثنا أبو بكر بن أبي شيبة حدثنا معاذ بن معاذ عن حميد عن عبد الله بن شقيق العقيلي قال
عن صلاة رسول الله ﷺ بالليل فقالت كان يصلي ليلا طويلا قائما وليلا طويلا قاعدا فإذا قرأ قائما ركع قائما وإذا قرأ قاعدا ركع قاعدا
Muslim narrated it in the Book of the Prayer of Travelers, chapter on the permissibility of performing voluntary prayer standing or sitting and performing part of a rakat, 730, from Ibn Abu Shayba with the same wording, standing, and part of it sitting.