Sunan an-Nasa'i 802
It was narrated that Anas said:
"The Messenger of Allah (ﷺ) entered upon us and the only people present were myself, my mother, the orphan and Umm  Harh, my maternal aunt. He said: 'Stand up and I will lead you in prayer.' It was not the time for a (prescribed) prayer. And he led us in prayer."
أَخْبَرَنَا سُوَيْدُ بْنُ نَصْرٍ، قَالَ أَنْبَأَنَا عَبْدُ اللَّهِ بْنُ الْمُبَارَكِ، عَنْ سُلَيْمَانَ بْنِ الْمُغِيرَةِ، عَنْ ثَابِتٍ، عَنْ أَنَسٍ، قَالَ دَخَلَ عَلَيْنَا رَسُولُ اللَّهِ صلى الله عليه وسلم وَمَا هُوَ إِلاَّ أَنَا وَأُمِّي وَالْيَتِيمُ وَأُمُّ حَرَامٍ خَالَتِي فَقَالَ ‏
"‏ قُومُوا فَلأُصَلِّيَ بِكُمْ ‏"‏ ‏.‏ قَالَ فِي غَيْرِ وَقْتِ صَلاَةٍ - قَالَ - فَصَلَّى بِنَا ‏.‏