Whenever the Messenger of Allah ﷺ prayed the morning prayer, he would remain seated in his place of prayer until the sun rose Hasna.
حدثنا أبو سعيد عن سفيان حدثني سماك يعني ابن حرب
كان رسول الله ﷺ إذا صلى الغداة جلس في مصلاه حتى تطلع الشمس حسناء
Its chain of transmission is sahih, it has already appeared at 20713.