Dronacharya was guru of Kurav and pandava's his son was Ashwathama
.
.
.
.
.
When in 1192, Prithveeraaj Chauhaan lost the battle from Mohammad Gauree, he left for jungle. There he met one old person with a scar on his head. Being a very good doctor Prithveeraaj Chauhaan confidently asked him that he can cure his scar. The old man agreed. But even after week's medication it remained as it is. Prithveeraaj was surprised and understood the details. He asked old man if he is Ashwatthaamaa. Because only the scars that is created through taking up the "MANI" the gem from forehead cannot be cured. The old man told that he was Ashwatthaamaa and then he went away. This description is given in "Prithviraj Raso" the book written in 12th century.