[1] She was the sixth child and third daughter of Crown Prince Frederick of Denmark and his wife Louise of Sweden.

In 1901, at the age of 21, Princess Thyra began a romantic relationship with a young court physician, Niels C. Ilsøe.

When it was discovered that Thyra had grown romantically attached to a royal servant, he was promptly dismissed and moved to West Jutland where he worked as a general practitioner.

He never married and, according to his family, he kept a picture of Princess Thyra on his nightstand for the rest of his life.

In 1922, however, Thyra’s younger sister, Princess Dagmar was allowed to marry a member of the lesser nobility, as social norms had changed over the years.