Sahih Bukhari Volume 1, Book 10, Hadith 861

حَدَّثَنَا إِسْمَاعِيلُ، قَالَ حَدَّثَنِي مَالِكٌ، عَنْ إِسْحَاقَ بْنِ عَبْدِ اللَّهِ بْنِ أَبِي طَلْحَةَ، عَنْ أَنَسِ بْنِ مَالِكٍ، أَنَّ جَدَّتَهُ، مُلَيْكَةَ دَعَتْ رَسُولَ اللَّهِ صلى الله عليه وسلم لِطَعَامٍ صَنَعَتْهُ، فَأَكَلَ مِنْهُ فَقَالَ ‏"‏ قُومُوا فَلأُصَلِّيَ بِكُمْ ‏"‏‏.‏ فَقُمْتُ إِلَى حَصِيرٍ لَنَا قَدِ اسْوَدَّ مِنْ طُولِ مَا لُبِسَ، فَنَضَحْتُهُ بِمَاءٍ فَقَامَ رَسُولُ اللَّهِ صلى الله عليه وسلم وَالْيَتِيمُ مَعِي، وَالْعَجُوزُ مِنْ وَرَائِنَا، فَصَلَّى بِنَا رَكْعَتَيْنِ‏

Narrated By Anas bin Malik : My grandmother Mulaika invited Allah's Apostle for a meal which she had prepared specially for him. He ate some of it and said, "Get up. I shall lead you in the prayer." I brought a mat that had become black owing to excessive use and I sprinkled water on it. Allah's Apostle stood on it and prayed two Rakat; and the orphan was with me (in the first row), and the old lady stood behind us and prayed two rakat with us.