Philip of Naples and Sicily, Duke of Calabria (13 June 1747 – 19 September 1777) was the eldest son and heir of Charles III of Spain, but was excluded from the succession to the thrones of Spain and Naples due to his imbecility. His younger brothers, Charles IV of Spain and Ferdinand I of the Two Sicilies replaced him in the succession. When his father became King of Spain in 1759, Philip remained in Naples where he lived until his death from smallpox at the age of thirty.

Born at the Reggia di Portici (Palace of Portici) in the Kingdom of Naples, he was the sixth child and eldest son of Charles VII and V, then King of Naples and Sicily, and his wife Maria Amalia of Saxony. His birth was a joyful event since his parents previously had five princesses, three of whom had died in childhood. The Prince was baptized Filippo Antonio Gennaro Pasquale Francesco de Paula. His grandfather, King Philip V of Spain, in whose honor he was named, had died on 9 July 1746. The child's godparents were his paternal uncle and aunt, King Ferdinand VI of Spain and Barbara of Portugal. As the heir apparent to his father, he was given the title of Duke of Calabria; a style that was created at the time for the heir apparent of the Kingdom of Naples. Although he was born plump and rosy, it was soon evident that there was something wrong with him. His wet nurses had to be changed several times and the child suffered from epileptic fits. As he grew up, it was confirmed that he had disabilities, especially by his peculiar face. According to one observer, the prince suffered from "a great heaviness of head, which makes him gloomy and ill-humored".

In 1754, the ambassador of Sardinia reported that " the prince royal does not appear to enjoy good health" adding that "there is something in his eyes that does not harmonize with the rest of his features. I have been assure[d] that although he is seven years old he does not speak, and that he can scarcely utter a word." However, his parents tried to conceal his deficiencies both from the public and from themselves making the child appear in court ceremonies as if there was nothing wrong with him. Until the age of seven Philip remained with his sisters and younger brothers under the care of a governess. In 1755, he was placed with his brother Charles under the tutorship of the Prince of San Nicandro.

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