The Child who is a Saalik can help his parents in their graves. The Saalik son is one of the three good deeds of the departed that remain in this world to multiply rewards he will receive in the hereafter.
Do not forget to make dua for your parents and to give charity on their behalf after they have passed away. They need it more now then ever.
May Allah enter them in Jannah Al Firdaus. Ameen. (MNY)