Delhi, India (CNN)Manju Gaur climbs the staircase with a fierce but steady determination. The building is decrepit, some walls crumbling, others caked in a thin, greasy film.
Just ahead of her is a row of police officers. Some from her native Assam state; others from this working class neighborhood in West Delhi.
A few steps behind her are a handful of social workers and coordinators from Bachpan Bachao Andolan, a local charity that has rescued thousands of children from human trafficking.
But Gaur -- a victim of trafficking herself -- is here on a much more personal mission: Finding her little sister.