Neighbor influenced my sister to run away from home

Sir, Last month i.e in March 2015 my sister in laws marriage was fixed but to my dismay just before few days she absconded from house on the support from my neighbour along with her son however she returned back next day after I did police complain. On her return she revealed that the boy's mother, his sister had mind washed her brain to run away from house. I have the audio record in which the boy has accepted this. Now that her marriage got postponed the boy is not willing to marry her and the result is that the girl is suffering. Is there any way in law that she can get justice?