Maybe those aghoris have done black magic on ur sister.
I myself have intense meditation practice.I know those aghoris are raping ur sister in shuksma world(astral world) ie the world made of thoughts in which u enter in ur dreams unconciously or thru meditation conciously. U cant stop this unless a divine power stops them(aghoris) to this.Only shirdi sai baba would listen to ur prayers fast.
I would request u to go nearby shirdi sai temple or the best thing would be to go shirdi and tell baba everything in front of his samadhi.Sai baba will definitely hear ur prayers.
OR
u could bring the vibhuti of lord sai from shirdi or any sai temple and give ur sister to eat that vibhuti with water nd pray lord sai whole heartedly to solve ur problem.
Lord sai is the avatar of lord dattatreya and he can remove all black magics.
Please pay heed to my words.GO TO THE SHARAN OF SHIRDI SAI