Following the death of his father, he became the head of one of the most prestigious Belgian noble families. Prince Baudouin was the elder son of Eugène II, 11th prince de Ligne, and Philippine de Noailles. He had a youngest brother, Antoine, and two sisters (Isabelle and Yolande). Following his death in 1985 without descent, his brother Antoine succeed him 13th Prince of Ligne and of the Holy Roman Empire.
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