Authentic
graded by Al-Albani
Mishkat al-Masabih 1689
وَعَنْ سَعِيدِ بْنِ الْمُسَيَّبِ قَالَ: صَلَّيْتُ وَرَاءَ أَبِي هُرَيْرَةَ عَلَى صَبِيٍّ لَمْ يَعْمَلْ خَطِيئَةً قَطُّ فَسَمِعْتُهُ يَقُولُ: اللَّهُمَّ أَعِذْهُ مِنْ عَذَابِ الْقَبْر. رَوَاهُ مَالك
Sa'id b. al-Musayyib said he prayed behind Abu Huraira at the funeral of a boy who had never sinned and heard him say, “O God, protect him from the punishment in the grave.” Malik transmitted it.
Reported by Malik (No. 540). Cited in Mishkat al-Masabih (No. 1689).