Where did I say she was named a princess? No where. I said she was named Marie, the source of which is several websites including
Princess Thyra of Denmark - Biography - The Biographicon. She was adopted and renamed, but the name was reported as being Marie. Thyra did have six children with Ernst, eldest of whom was also named Maria. But I never mentioned at all that Marie was given the title princess.
Thyra had with Ernst
Princess Maria Louise (not the Marie above) who married Prince Maximillian of Baden and had two children
Prince George William- died in a car accident sadly on the way to the funeral of Frederick VIII of Denmark's funeral, his Uncle, not married.
Princess Alexandra: married the Duke of Mecklenberg-Schwerin and had five children, including a Princess Thyra who died in 1981
Princess Olga- died unmarried
Prince Christian- died of appendicitas and perionitas at age 16
Prince Ernst Augustus-succeeded his father as Duke, married and had five children
But my point had nothing to do with the illegitamite daughter, who I never said was called a princess. My point was you were wrong, that Princess Thyra, daughter of Christian IX was the last holder of the name. Yes, the suicide of her lover is sad. But her niece and namesake Princess Thyra, daughter of Friedrick VIII, born 27 years after her, is the last person in the direct Danish royal family with the name. And more indirect, her grandaughter from her daughter Alexandra, also holds the name (though this is a German princess and not a Danish). So if Friedrick would name his daughter Thyra even knowing the history of his sister, it is not unlikely that the name would pop up once again.