Monsieur d'Orléans (16 April 1607 – 17 November 1611) was the second son and fourth child of Henry IV of France and his consort, Marie de' Medici. Commonly ascribed the names Nicolas or Nicolas Henri and the title Duke of Orléans, he was neither baptised nor invested as such during the course of his short life. He was betrothed to Marie de Bourbon-Montpensier, heiress to vast lands of the extended House of Bourbon. After his father's death in 1610, he was heir presumptive to his older brother, Louis XIII. Of frail health, he died of seizures brought on by hydrocephalus at the age of four, whereupon his title and betrothal were transferred to Gaston, his younger brother. Biography Birth and name Marie de' Medici gave birth to her fourth child, a son, at the Palace of Fontainebleau. Like all of her other children, he was born in the Oval room, later called the "Louis XIII salon". Born at 22:00 on 16 April 1607, the day after Easter, the prince's birth was a source of tremendous joy for his father, King Henry. His newborn son was said to resemble him, possessing the same large nose and "sparkle of his father's eyes". At his birth, Henry bestowed upon his son 10,000 Lt in land revenue, adding that he would be granted an annuity provided that he should he serve his brother, the Dauphin, well. As it had become customary for the second son of the king to receive the title of Duke of Orléans, news of the young prince's birth described him as "Monsieur d'Orléans". Henry expressed no desire for this to be retracted, but specified that his son will only be styled as such, not invested. Monsieur d'Orléans, as he was henceforth known, was never invested as Duke of Orléans and never baptised; thus, he was never given a name. It was not uncommon in the French royal family for children to be baptised when they were much older: the Dauphin himself had only been baptised in September 1606, when he was almost 5. This lack of a name is also evidenced by his death register, which only records him as "Monseigneur le duc d'Orléans". He was similarly referred to by his doctor during his final illness, where no name was mentioned. In his genealogy of French royalty, Père Anselme refers to Monsieur d'Orléans as "N... de France, duc d'Orléans". While