Being afflicted with grief for the death of his son, he performed great asceticism, to get a child who would be immortal. He obtained such a son.
स पुत्रशोकादुद्विग्नस्तपस्तेपे सुदुष्करम्। भवेन्मम सुतोऽमर्त्य इति तं लब्धवांश्च सः॥