Trouble with landlord: electricity turned off

My sister is currently renting an appartment in new york, she has had a lot of trouble with her landlord who lives down stairs from her. This morning her electricity was turned off because the landlord hasn't paid his bill since march. She has two children living with her also. I also just found out that it might be an illegal apartment but she has been there for about 4 years. Is there anything she can do to get the electricity turned on? She has paid her rent every month and the landlord is responsible for the electricity. She is a single mother who also dosn't get child support for one of her kids so she doesn't have money. Any advice you could give me to help her out would be very appreciated.

Thank you,

Call the city's 311 line and file a polce report; also call the electric company and try to have the power restored in her own name if possible--and sue the LL in small claims for costs, damages etc