As court painter to Philip IV, Velázquez painted countless portraits of the king and his family, images at once majestic and human. This charming, child-size version of the traditional royal portrait may commemorate the swearing of allegiance by the nobles of Castile to the two-year-old heir to the throne. Baltasar Carlos is shown standing regally still beside one of the lively dwarves who served as jesters and companions at the Spanish court. The dwarf's rattle and apple can be interpreted both as playthings appropriate to the prince's age and as symbols of the orb and scepter he will someday wield as king of Spain.