Psychology- Mother and Daughter trapped?

You have been seeing a 10 year old girl named Mary for a couple of months, and from the beginning, she has been very quiet and unwilling to open up about her personal life. She came without her mother or father's knowledge. In one of her sessions, she lifted her hand to fidget with her hair, and you caught a glimpse of a bruise near her elbow as her sleeve shifted. You asked her where they came from, and she was very hesitant, almost afraid to tell the truth. As the sessions continued, she began to open up more after you encouraged her to talk about the bruises, and it turned out that her father sexually abused her while her mother appeared to turn a blind eye to prevent being abused herself.

One day, the mother was confronted by the father about why Mary doesn't not come home from school straight away, Mary's mother followed her after school to the Practice and burst into the room with a look of worry and panic about whether Mary had told you what had been happening at home. You persuade the mother to sit down and ask her to tell you the life she is living, she snaps at you saying it is none of your business and what her daughter had been saying was all lies. Before Mary gets pulled out she quickly tells you to not tell anyone about their current way of living because her mother loves the father and to be separated from him would devastate her. Mary's future is in your hands. What should you do?