Rostam was unaware that he had a son, Sohrab, by Princess Tahmina. He had not seen the Princess for many years. After years without any real knowledge of one another, Rostam and Sohrab faced each other in battle, fighting on opposing sides. Rostam did not recognise his own son, although Sohrab had suspicions that Rostam may be his father.
They fought in single combat and Rostam wrestled Sohrab to the ground, stabbing him fatally. As he lay dying, Sohrab recalled how his love for his father – the mighty Rostam - had brought him there in the first place. Rostam, to his horror, realised the truth. He saw his own arm bracelet on Sohrab, which he had given to Tahmina many years before and which Tahmina had given to Sohrab before the battle, in the hope that it might protect him.
But he realised the truth too late. He had killed his own son, ‘the person who was dearer to him than all others’. This is one of the most tragic episodes of the Shahname.