Ash-Sha'bi said: "I was informed by one who saw the Prophet: He (pbuh) saw a solitary grave, s he lined his Companions (behind him) to pray over it." It was said to him (Ash-Sha'bi): "Who informed you?" He said: "Ibn Abbas."  

أَخْبَرَنِي مَنْ رَأَى النَّبِيَّ ﷺ وَرَأَى قَبْرًا مُنْتَبِذًا فَصَفَّ أَصْحَابَهُ خَلْفَهُ فَصَلَّى عَلَيْهِ فَقِيلَ لَهُ مَنْ أَخْبَرَكَهُ فَقَالَ ابْنُ عَبَّاسٍ قَالَ وَفِي الْبَابِ عَنْ أَنَسٍ وَبُرَيْدَةَ وَيَزِيدَ بْنِ ثَابِتٍ وَأَبِي هُرَيْرَةَ وَعَامِرِ بْنِ رَبِيعَةَ وَأَبِي قَتَادَةَ وَسَهْلِ بْنِ حُنَيْفٍ  

"Umm Sa'd died while the Prophet was absent. So when he arrived he performed Salat over her, and a month had already passed."  

أَنَّ أُمَّ سَعْدٍ مَاتَتْ وَالنَّبِيُّ ﷺ غَائِبٌ فَلَمَّا قَدِمَ صَلَّى عَلَيْهَا وَقَدْ مَضَى لِذَلِكَ شَهْرٌ