This movie was sequel to film "Siostra" because movie "Agata" was cancel.
Character named Karol Rojek won't return in this movie.
The movie is set ten years after the events of the first film "Siostra"
Character named Laura Strauss is reference to composer Johann Strauss .
In the movie, main character is Marek's daughter, Gosia. Previously in "Siostra" Marek, her dad was the main character.