Between Google translate and my own limited knowledge of the period I am almost certain that this is art of Romanian Crown Princess - shortly thereafter Queen - Marie of Edinburgh, wife of Crown Prince Ferdinand, and their first daughter Elisabeta in the uniform of the 4th Rosiori Regiment in 1904. One can in fact find a fairly decent amount of photographs of Queen Marie in the 4th Rosiori uniform on the web:
I'm inclined to think that this may have just been a mistaken caption on the part of the original photo because their respective ages appear about right for Elizsaveta and Carol, while Marie is very obviously younger in other photos from around that time.