His paternal grandparents are King Constantine II of Greece and Queen Anne-Marie, born a Princess of Denmark. His maternal grandparents are Robert and Chantal Miller. He was christened at the Greek Cathedral of St. Sophia, Bayswater, London, England, on 7 June 2001. His godparents are Princess Theodora of Greece, Infanta Elena of Spain, Prince Alexandré zu Furstenberg, Crown Prince Kardam of Bulgaria, Princess Rosario of Bulgaria, Prince Guillaume of Luxembourg, and Veronica Toub. He was named partially for the Greek hero, Achilles.