Princess Helena Victoria of Schleswig-Holstein, informally known by her family as Thora, was a granddaughter of Queen Victoria of the United Kingdom. From July 1917, she was addressed simply as Prince
Late 1880s portrait of the young princess
Princess Marie Louise of Schleswig-Holstein was a granddaughter of Queen Victoria.
Portrait by James Lafayette, c. 1910–1915
Princess Marie Louise in the 1890s