Isabella von Thurn und Valsássina-Como-Vercelli

Countess Isabella Maria von Thurn und Valsássina-Como-Vercelli (12 February 1962 – 29 November 1988), styled upon her marriage as Princess Ludwig Rudolph of Hanover, was an Austrian model, socialite, and noblewoman. She was a princess of the House of Hanover through her marriage to Prince Ludwig Rudolph of Hanover. She died of a drug overdose in 1988, which reportedly led to her husband's suicide later that day.

Biography
Isabella was the daughter of Count Ariprand Raimund von Thurn und Valsássina-Como-Vercelli (1925–1996) and Princess Maria Perpetua Euphemia von Auersperg (b. 1929), both members of the defunct Austrian high nobility. By birth she was a member of the House of Thurn und Valsassina, a Carinthian branch of the House of Torriani that ruled Milan in the 13th and 14th century, before being ousted by the Visconti family. She worked as a fashion model before getting married. She spent her childhood between Burg Bleiburg and Castle Hagenegg, which were both owned by her family.

Marriage and family
She married Prince Ludwig Rudolph of Hanover on 4 October 1987 at her family's castle in Bleiburg. Isabella and Ludwig were distantly related (7th cousins), both sharing descent from Charles Alexander, Duke of Württemberg and his wife, Princess Marie Auguste of Thurn and Taxis. The couple had one son, Prince Otto Heinrich Ariprand Georg Johannes Ernst August Vinzenz Egmont Franz of Hanover, who was born on 13 February 1988 in Gmunden.

Death
In the early hours of 29 November 1988, after the couple had entertained guests at their home, Königinvilla (The Queen's Villa) in Gmunden, a house left to them by Ludwig's elder brother Ernst August, the prince went to the bedroom where his wife had retired before midnight, and found Isabella sprawled fully dressed across their bed. The efforts of her husband and friends to revive her proved futile. Ludwig Rudolph, who had been investigated previously on suspicion of illegal drug purchases, placed a call to his brother, Ernst August, in London, imploring him to take care of the couple's 10-month-old son. As authorities removed Isabella's body and investigated the scene, discovering syringes, cocaine and heroin, Ludwig Rudolph slipped away. Hours later, the prince was found in his car near his family's hunting lodge several miles away, on Lake Traun. He had the muzzle of a rifle in his mouth and was dead of a gunshot wound.

The case was closed without further investigation, although authorities announced her death was likely caused by a cocaine overdose. Isabella Maria and Ludwig Rudolph were interred on 2 December 1988 at Grünau im Almtal, Austria, having been married less than 14 months. Custody of their infant son Otto was awarded, contrary to the expressed wishes of Ludwig Rudolph, to the child's maternal grandparents. He was raised at their castle, Schloss Bleiburg, in Austria, and then studied art at Braunschweig University of Art in Brunswick (Braunschweig). He currently lives with his grandmother in Salzburg.