'A'isha reported that the Messenger of Allah ﷺ would pray in the night for a long time, and when he prayed standing be bowed in a standing posture, and when he prayed sitting, he bowed in a sitting posture. (Using translation from Muslim 730b)
كَانَ رَسُولُ اللهِ ﷺ «يُصَلِّي لَيْلًا طَوِيلًا فَإِذَا صَلَّى قَائِمًا رَكَعَ قَائِمًا وَإِذَا صَلَّى قَاعِدًا رَكَعَ قَاعِدًا»