German-British-Swedish princess, noted as the mother of the current King of Sweden, Carl XVI Gustaf. A member of the House of Saxe-Coburg and Gotha, Sibylla became a Swedish princess by marrying Prince Gustaf Adolf, Duke of Västerbotten, who did not live to ascend the Swedish throne.
She was the elder daughter and second child of Charles Edward, Duke of Saxe-Coburg and Gotha, and Princess Victoria Adelaide of Schleswig-Holstein. Through her father, she was a great-granddaughter of Queen Victoria of the United Kingdom. Her paternal grandfather was Prince Leopold, Duke of Albany, the youngest son of Queen Victoria and Prince Albert.
On 19 October 1932 in Coburg, Sibylla married her second cousin Prince Gustaf Adolf of Sweden, Duke of Västerbotten, in a civil ceremony, followed by a church wedding the day after. Gustaf Adolf was the eldest son of Crown Prince Gustav Adolf of Sweden (later Gustaf VI Adolf) and Princess Margaret of Connaught, a granddaughter of Queen Victoria. Both Sibylla and Gustaf Adolf were great-grandchildren of Queen Victoria. The couple had five children. Sibylla never became Crown Princess herself since her husband died before his father and his grandfather King Gustav V.
Sibylla became a widow in 1947 when Gustaf Adolf died in an airplane crash at the Copenhagen Airport in Denmark. Their only son, Carl Gustaf, became second-in-line to the throne at the age of nine months and, later, Crown Prince at the age of four.
Sibylla died in Stockholm of cancer on 28 November 1972 at age 64, less than a year before her son ascended to the throne.
Link to Wikipedia biography