Al-Kāfi - Volume 7 > Things that Reach a Deceased after his Death
Hadith #3

3- عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنِ ابْنِ أَبِي عُمَيْرٍ عَنْ إِسْحَاقَ بْنِ عَمَّارٍ عَنْ أَبِي عَبْدِ اللهِ (عَلَيْهِ السَّلام) قَالَ لا يَتْبَعُ الرَّجُلَ بَعْدَ مَوْتِهِ إِلا ثَلاثُ خِصَالٍ صَدَقَةٌ أَجْرَاهَا للهِ فِي حَيَاتِهِ فَهِيَ تَجْرِي لَهُ بَعْدَ مَوْتِهِ وَسُنَّةُ هُدًى سَنَّهَا فَهِيَ يُعْمَلُ بِهَا بَعْدَ وَفَاتِهِ وَوَلَدٌ صَالِحٌ يَدْعُو لَهُ.

3. Ali ibn Ibrahim has narrated from his father from ibn abu ‘Umayr from Ishaq ibn ‘Ammar who has narrated the following: “Abu ‘Abd Allah, ‘Alayhi al-Salam, has said, ‘Nothing follows a deceased after his death except three things: a charity that Allah has made to function in his life time which continues after his death, a Sunnah of guidance that one establishes which is acted upon after his death and virtuous children who pray for him.’”