Thetis, the daughter of Nereus and Doris, was so beautiful that Jupiter himself sought her in marriage; but having learned from Prometheus the Titan that Thetis should bear a son who should grow greater than his father, Jupiter desisted from his suit and decreed that Thetis should be the wife of a mortal. By the aid of Chiron the Centaur, Peleus succeeded in winning the goddess for his bride and their son was the renowned Achilles. In our chapter on the Trojan war it will appear that Thetis was a faithful mother to him, aiding him in all difficulties, and watching over his interests from the first to the last.