Philip, Hereditary Prince of Portugal
Philip was the Hereditary Prince of Portugal from 1537 to his death in 1539. He was the sixth child and third son of king John III of Portugal and Catherine of Austria.
In 1537, he succeeded his brother Prince Manuel as Prince of Portugal, after his premature death.
After Philip's own premature death two years later, after reaching six years old, his younger brother Infante João Manuel became the next Prince of Portugal.