The sitter in this charming portrait can be identified as the Infante Felipe Próspero due to the numerous amulets that hang from his belt. The first son of Philip IV of Spain and his second wife Mariana of Austria, he was a sickly child and it was believed that these would ward off the evil eye, protecting him from infection. The artist has taken as his inspiration Velazquez’s portrait of 1659, which similarly shows the young Prince with his protective charms, arm outstretched (Vienna, Kunsthistorisches Museum). Sadly, the great care that was lavished on the child could not prevent his death at the age of four. The affect this had on the King is clear from a letter to his friend Sister Maria, Abbess of Ágreda. ‘The long illness of my son and my constant attendance at his bedside have prevented me from answering your letter, nor has my grief allowed me to do so, until today. I confess to you, Sor María, that my grief is great, as is natural after losing such a jewel as this.’ (M. Hume, The court of Philip IV: Spain in decadence, London, 1907, p. 491.)