Prince Baudouin of Belgium

Prince Baudouin of Belgium (3 June 1869 – 23 January 1891), born in Brussels, was the first child and eldest son of Prince Philippe, Count of Flanders, and his wife, Princess Marie of Hohenzollern-Sigmaringen.
Baudouin was the nephew of Leopold II of Belgium. Upon the death of Leopold, Duke of Brabant, Leopold II's eldest (and only) son, six months before Baudouin's birth, the king was left with only one person in the line of succession – Leopold II's younger brother, Prince Philippe, Count of Flanders.
Baudouin's birth in June 1869 was celebrated throughout the country. He was second in line to the throne at the time of his birth, after his father. King Leopold II was to have one more child, another daughter, Clémentine. Prince Baudouin was thus groomed to eventually succeed his uncle as king.
After Prince Baudouin's death, his younger brother, Albert, eventually became heir presumptive after the death of their father, and later succeeded their uncle Leopold II as Albert I of Belgium.
Death.
Baudouin died in the Palace of the Count of Flanders on 23 January 1891, a day after the anniversary of his cousin Leopold's death. Baudouin had been visiting his sick sister, Henriette. The prince, who had been suffering a bout of influenza, insisted on staying with his sister. Rumours circulated after his death that foul play had been involved, including a suggestion that Baudouin's death was a copy of the suicide of Crown Prince Rudolf of Austria; Rudolf was the husband of Baudouin's cousin, Stéphanie. Baudouin was, at the time of his death, soon to be betrothed to his cousin, Clémentine.
Upon the death of Prince Baudouin, the Belgian Parliament was adjourned and theatres and public institutions were closed until after the funeral. Baudouin's body was interred at the royal vault at the Church of Our Lady of Laeken in Brussels.
After Baudouin's death, his younger brother, Albert, eventually became heir presumptive after the death of their father, and later succeeded their uncle Leopold as Albert I of Belgium.