Princess Lilian of Sweden

Princess Lilian of Sweden, whose relationship with Prince Bertil was kept secret for more than 30 years because she was a commoner, died at her home in Stockholm Sunday, the Associated Press reports. She was 97. No official cause of death was released by the Royal Palace; however, she had suffered from Alzheimer's Disease and had been in poor health in recent years, according to the AP.

Born Lilian Davies in Swansea, Wales, Lilian eventually moved to London to pursue a career as an actress and model. She married British actor Ivan Craig in 1940. During World War II, while Craig was serving in the British army, Lilian worked at a factory making radio sets, as well as at a hospital in London.

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In 1943, she met Sweden's Prince Bertil, who was stationed at the Swedish Embassy in London. She and Craig, who had also fallen in love with someone else while serving abroad, subsequently divorced amicably, but Lilian and Bertil could not make their relationship public because the idea of a potential heir to the Swedish throne marrying a divorced commoner was taboo. His father, King Gustaf VI Adolf, prevented the two from marrying because it would put their dynasty in jeopardy.

Lilian and Bertil settled for a common-law marriage and lived together in France and Stockholm, though their relationship was never made official. Finally, in 1976, a new king gave them permission to get married, which they did in December of that year. Lilian was 61 at the time and Bertil was 64.

The couple never had children, and Prince Bertil died at their home in 1997. Lilian continued to make appearances on behalf of the royal family, but stopped doing so in recent years due to health issues.