The first being her eldest sister, Minka. They never really got along, and Minka has since become a radical human activist. It would would be right up her alley to travel to Amsterdam, and protest the existence of all those evil creatures, like what her little sister has become. I sorta had Evan Rachel Wood in mind for the pb.
Then there is Victoria, she is Jun's younger sister, the one she was closest to. They had a very good bond, but when Jun turned out to be a were, she was forbidden from seeing her. Victoria is now well above age, and rightfully has flown the coop. For her, I was picturing Imogen Poots.